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_____________________________________________________________________________________1Lab14:QualitativeOrganicAnalysisWrittenbyDanielleM.SolanoDepartmentofChemistry&BiochemistryCaliforniaStateUniversity,BakersfieldObjectivesBytheendofthislaboratory,youshouldhavedevelopedtheskillstodothefollowing:• Determinethefunctionalgroupofanunknowncompoundbyusingclassificationtests.• Understandthepurposeofasyntheticderivative.BackgroundOrganicchemistsoftenmustidentifyunknowncompounds.Insomecases,suchasareaction,youmayhaveagoodideaofwhatthecompoundinquestionis.Howeverinothercases,suchaswhenyouisolateacompoundfromanaturalsource,youmayhavenoideawhatthecompoundmightbe.Inthisexperimentyouwilldeterminetheidentityofanunknowncompound.First,youwillneedtopurifyyourcompound,thenyouwillneedtoidentifyitsfunctionalgroup(itwillcontainonlyone),andfinallyyouwillneedtomakeaderivativeofthecompound.Youwillconfirmyourresultswithboilingormeltingpoint,IR,andNMR.Impuritiesinyourcompound willmake itextremelydi fficulttoidentify.Thus,be foreyoudoanythingelse,youwillneedtomakesureyourunknowncompoundispure.Considereachofthefollowingpurificationtechniquesyouhavelearnedoverthecourseoftheyear.1. Recrystallization:Workswellfors olidcompounds .Youwilln eedtofindanap propriaterecrystallizationsolvent.Consideravarietyofsolventsandmixedsolventsystems.2. Distillation:Workswellfor liquidsthatha veaboiling pointof<250°C.(Note :Fractionaldistillationmayberequiredifyou suspectimp urities closetotheboilingpointof yourunknown.)3. ColumnChromatography:WorkswellforUVactivecompounds.YouwillneedtouseTLCtoidentifyasolventsystemthatwillseparateyourunknownfromanyimpurities.Afteryouhavepurifiedyourunknown,verifythatitispureenoughtoproceedbymeasuringtheboilingormeltingpoint.Notethatwhileyouwillnotknowwhatthemeltingpointorboilingpointofyouru nknownshoul dbe,thenarrow nessisanexcellentindicatorof whetheror notyour productispure.Alsopayattentiontotheappearanceofyourunknownandseeifithaschanged(hopefullyforthebetter)duringthecourseofthepurificationprocess.Onceyourunknownispure,youwillneedtoidentifyitsfunctionalgroup.Yourunknownwillhaveonemajorfunctionalgroup(alcohol,ketone,aldehyde,amide,amine,carboxylicacid,orester).Additionally,yourunknowncompoundmayormaynotcontainanaromaticring.Todeterminethe

functionalgroup,itisrecommendedthatyoustartwithsolubilitytests,andthenconductfunctionalgroupclassificationtests.IRspectroscopymayalsobeusefulatthispoint.Solubilitycansometimesprovideasurprisinglyusefulamountofinformation.First,youwilltestyourunknown'ssolubilityinwater.Compoundswith4carbonsorlesswilleasilydissolveinwater,whereascompoundswith8carbonsormorewillbeinsoluble.Compoundscontaining5-7carbonsmayormaynotdissolve(oftentheywilldisplay-partial-solubility).Ifyourcompounddissolvesinwater,youwillals owanttoche ckthepHof thesolution. Amineswill typically bebasic,andcarboxylicacidswilltypicallybeacidic.Mostothercompoundswillbeneutral.Compoundsthatareinsolubleinwatershouldthenbesubjectedtoasolubilitytestin5%HCl.Typically,onlyamineswillbesolubleinHClbecausetheyformwater-solublehydrochloridesaltswhentheyreactwithHCl.CompoundsthatarenotsolubleinHCl,shouldbesubjectedtotestinginbasicsolutions(5%NaOHand 5%NaHCO3).Both strongandwe akacids(Carboxy licacidsa ndphenols)will bedeprotonatedbyNaOHtoformwater-solublealkoxides.OnlystrongacidslikecarboxylicacidswillreactwithNaHCO3.Compoundsthatarenotsolubleinbaseshouldthenbereactedwithaverystrongacid,sulfuricacid(notethatinthecaseofsulfuricacid,-solubility-isalsoindicatedbyanytypeofreactionsuchasheat,gasgeneration,oracolorchange).Compoundsthatcannotbecomeprotonatedbysulfuricacidatall(i.e.,alkanes,alkylhalides,andaromaticcarbons)willstillremaininsoluble.Thesesolubilitytestsaresummarizedintheflowchartsbelow.Theresultsfromthesolubilitytestscansignificantlyhelpindeterminingwhichclassificationtestsshouldthenbeperformed,oratleastnarrowdownthelist.Bynomeansdoyouneedtoconductallclassificationtests.Infact,youshoulddoyourbesttoselectonlyteststhatwillprovideyouwithadditionalinformationaboutyour unknownand/orconfirmresults. Also,makes urethatyou rglasswareiscleananddrysoyoudonotgetanyfalsepositiveorfalsenegativeresults.Keepinmindthatanegativeresultforaclassificationtestprovidesusefulinformation,sobesuretokeeptrackofnegativ eresults aswellaspositiveresu lts.Also,foreachcl assifica tiontestthatyouWater Soluble

Compounds

pH > 8 pH < 5 pH 5-8

Low MW basic (i.e., amines)

Low MW acidic (i.e., carboxylic acids)

Low MW neutral (contains an N or O)

Water Insoluble

Compounds

Soluble in

5% HCl

High MW basic (i.e., amines)

Insoluble in

5% HCl

Soluble in

5% NaOH

Insoluble in

5% NaOH

Soluble in 5% NaHCO

3

Insoluble in 5% NaHCO

3

Soluble in H

2 SO 4

Insoluble in H

2 SO 4

High MW strongly acidic

(i.e., carboxylic acids)

High MW weakly acidic

(i.e., phenols)

High MW Neutral

(does not contain an N or O)

High MW Neutral

(contains an N or O)

Lab14:QualitativeOrganicAnalysis_____________________________________________________________________________________ perform,besuretorunablank,andoneormorecontrols.Thesewillhelpyoutodetermineifareactionactuallyoccurred.Ablankincludeseverythingbuttheunknown,andacontrolincludesacompoundforwhichtheoutcomeisknowninplaceoftheunknown.Controlscanbepositive(acompoundyouknowwillre act)ornega tive(a compound thatyouknowwillnotr eact).Theclassificationtestsaresummarizedinthetablebelow.Functional Group Test Test No. Notes Alcohols Acetyl chloride C-1 Tests for the presence of alcohols Chromic acid C-9 Tests for the presence of 1° alcohols, 2° alcohols, & aldehydes Iodoform test C-16 Tests for -CH(OH)CH3 and -COCH3 groupings Lucas's test C-17 Used to classify alcohols as 1°, 2°, or 3° Aldehydes Benedict's test C-6 Tests for the presence of aldehydes Chromic acid C-9 Tests for the presence of 1° alcohols, 2° alcohols, & aldehydes 2,4-Dinitrophenylhydrazine C-11 Tests for the presence of aldehydes & ketones Tollen's test C-23 Tests for the presence of aldehydes Amides Alkaline hydrolysis C-2 Tests for the presence of amides & esters Elemental analysis C-12 Tests for the presence of nitrogens and halogens Amines Basicity test C-4 Used to distinguish alkyl amines from aromatic amines Bromine water C-8 Tests for the presence of phenols & aromatic amines Elemental analysis C-12 Tests for the presence of nitrogens and halogens Hinsberg's test C-15 Used to classify amines as 1°, 2°, or 3° Quinhydrone C-20 Used to classify amines as 1°, 2°, or 3° Aromatics Aluminum chloride & chloroform C-3 Tests for the presence of aromatic rings Carboxylic Acids Neutralization equivalent C-18 Provides information about the number of carboxylic acids and the MW Esters Alkaline hydrolysis C-2 Tests for the presence of amides & esters Ferric hydroxamate C-14 Tests for the presence of esters Ketones 2,4-Dinitrophenylhydrazine C-11 Tests for the presence of aldehydes & ketones Iodoform test C-16 Tests for -CH(OH)CH3 and -COCH3 groupings Phenols Bromine water C-8 Tests for the presence of phenols & aromatic amines Ferric chloride C-13 Tests for the presence of phenols

Lab14:QualitativeOrganicAnalysis_____________________________________________________________________________________ Atthispoint,youshouldbeabletouseyourboilingormeltingpointdatacombinedwiththeresultsofyourfunctionalgroupdatatodevelopahypothesisastowhatyourunknownmightbeoratleastnarrowdownthelisttoonlyafewcandidates.Notethatduetotheaccuracy(orlackthereof)ofourthermometers,yourboilingormeltingpointsmaybeupto15°Clowerthantheliteraturevalues.Onceyourfunctionalgrouphasbeendetermined,youwillprepareaderivativeofyourunknown.Toprepareaderivative,youwillselect asuitable reactionthat convertsyourunkno wninto adifferentfunctionalgroupforwhichtheboilingormeltingpointisknown.Thisisparticularlyusefulbecausecompoundsthathavesimilarboilingormeltingpointswilloftenhavederivativesthatdiffersignificantlyintermsofboilingormeltingpoint.Youshouldthenbeabletoidentifyyourunknownusingthisinformation.Finally,youcanconfirm theiden tityofyour productusingIRandNMR. Notethat thesemeasurementscanbetakenatanytimeduringthecourseofthelabafteryoupurifiedyourproduct.Infact,itisrecommendedthatyouconductthemsoonerratherthanlaterastheymayprovidevaluableinformationastotheidentityofyourunknown(e.g.,IRmayrevealyourfunctionalgroup).LabNotebookPreparationABeforecomingtolabonthefirstdayofthisexperiment,thefollowingitemsmustbeinyourlabnotebook:1. Titleofexperiment2. Datetheexperimentistobeperformed3. Outlineofyourplanfordeterminingtheidentityofyourunknown4. Hazardsofandappropr iatepre cautionsfor thesafehandlingofunknownorgan iccompounds5. ReferencesLabNotebookPreparationBBeforecomingtolabonthedayyouplantoprepareaderivative,thefollowingitemsmustbeinyourlabnotebook:1. Titleofexperiment2. Datetheexperimentistobeperformed3. Listofpossibleunknowns4. Thechemicalreaction(s)youareattempting(withskeletalstructures...Rgroupsareokayifyoudonotknowtheidentityofyourunknownyet)5. Foreachreactionyouareattempting,includeatablewithinformationaboutyourstartingmaterials.Includemolecularweight,molarequivalents,andmmolestobeused.Forsolidsincludegrams.Forliquids,includegrams,density,andvolume.Forsolutions,includetheconcentrationandvolume.(Note:Youwillnotbeabletocompletelyfillinthetableifyoudonotknowtheidentityofyourunknownyet.Ifthatisthecase,listwhateverdatayoucan.)

Lab14:QualitativeOrganicAnalysis_____________________________________________________________________________________56. Anyrelevantphysicalproperties(i.e.,meltingpointsorboilingpointsofpossibleunknownsandtheirderivatives)7. Hazardsofandappropriateprecautionsforthespecificreaction(s)youareconducting8. ReferencesSafetyNotes• Assumethatallunknownsareflammabl eandharmfulbyinhalation, ingestion, andskinabsorption.Donotinhaletheirvaporsandavoidcontactwitheyes,skinandclothing.Directions1. Purifyyourunknownusing distillatio n,recryst allization,o rcolumnchromatography.Itisrecommendedthatpurifytheentireunknownprovidedsothatyouhaveenoughpurematerialforallofthetests.2. Measuretheboilingormeltingpointofyourunknowntoconfirmitspurity.3. Confirmwithyourinstructorthattheboilingormeltingpointyouobtainedforyourunknowniswithin15°Cofthereportedliteraturevaluebeforeproceeding.4. Testthesolubilityofyourunknowninwater.(Ifyourunknownisasolid,crushitintoafinepowder.)a. Addapproximately30mgofyourunknowntoatesttubeorsmallvial.b. Add1mLofwaterandshakevigorouslyforapproximately30seconds.Iftheunknownappearstobesoluble,testthepHofthesolutionandthenskiptostep9.5. Testthesolubilityofyourunknownin5%HCl.(Ifyourunknownisasolid,crushitintoafinepowder.)a. Addapproximately30mgofyourunknowntoatesttubeorsmallvial.b. Add1mLof5%HClandshakevigorouslyforapproximately30seconds.Iftheunknownappearstobesoluble,skiptostep9.6. Testthesolubilityofyourunknownin5%NaOH.(Ifyourunknownisasolid,crushitintoafinepowder.)a. Addapproximately30mgofyourunknowntoatesttubeorsmallvial.b. Add1mLo f5%N aOHands hakevig orouslyf orapproximate ly30second s.Iftheunknownappearstobeinsoluble,skiptostep8.7. Testthesolubilityofyourunknownin5%NaHCO3.(Ifyourunknownisasolid,crushitintoafinepowder.)a. Addapproximately30mgofyourunknowntoatesttubeorsmallvial.b. Add1mLof5%NaHCO3andshakevigorouslyforapproximately30seconds.c. Notewhetheryourunknownissolubleorinsolubleandthenskiptostep9.

Lab14:QualitativeOrganicAnalysis_____________________________________________________________________________________68. TestthesolubilityofyourunknowninconcentratedH2SO4.(Ifyourunknownisasolid,crushitintoafinepowder.)a. Addapproximately30mgofyourunknowntoatesttubeorsmallvial.b. Add1mLofconcentratedH2SO4andshakevigorouslyforapproximately30seconds.c. Notewhetheryourunknownissolubleorinsoluble.(Anyindicationofareactionsuchasheat,gasgeneration,oracolorchangealsoindicatessolubility.)9. Conductclassificationtestsasneeded.Seedirectionsforspecifictestsbelow.10. Confirmtheidentityofyourfunctionalgroupwithyourinstructorbeforeproceeding.11. Prepareoneormorederivativesofyourunknown.Seedirectionsforspecificderivativesbelow.12. Measurethemeltingpointofanyderivatives.13. Confirmwithyourinstructorthatthemeltingpointyouobtainedforyourderivativeiswithin15°Cofthereportedliteraturevalue.14. TaketheIRandNMRofyourunknown.ClassificationTestsC-1AcetylChlorideThisreactiontestsforthepresenceofalcohols.Ifyoususpectthatyouhaveprimaryorsecondaryalcohol,useprocedureA.Ifyoususpectthatyouhaveatertiaryalcohol,useprocedureB(manytertiaryalcoholswillnotreactwithprocedureA).Notethataminesandphenolswillalsogiveapositiveresultforthistest.SafetyNotes:Acetylchlorideis verycorrosiveanditsvap orsarei rritatingand toxic.Itreactsviolentlywithwaterandsomealcohols.Workinafumehoodorunderasnorkelandkeepawayfromwater.N,N-Dimethylanilineandammoniaareharmfulifinhaledorallowedtocontacttheskin.Workunderinafumehoodorunderasnorkel.RecommendedControls:1-butanol,2-methyl-2-propanolProcedureA:1. Add10dropsoftheunknown(0.4gofasolid)toatesttube.2. Inthefumehoodorunderasnorkel,dropwiseadd10dropsofacetylchloride.3. Observeanyevolutionofheat,andholdapieceofpHpaperoverthetopofthetesttubetodetermineifanyHCIgaswasgenerated.4. Afteraminuteortwo,pourthemixtureintoabout2mLofwater,shakeit,andnoteanyphaseseparation.Cl

O OR O OHR HCl

Lab14:QualitativeOrganicAnalysis_____________________________________________________________________________________7Interpretation:Evidenceofreaction(heat,HCIgas),especiallyifaccompaniedbyphaseseparationindicatesanalcohol.ProcedureB:1. Inthefumehoodorunderasnorkel,mix5dropsofacetylchloridewith10dropsofN,N-dimethylaniline.2. Cautiouslyadd5dropsoftheunknown(0.2gofasolid).3. Warmthemixtureona50°Cwaterbathfor15minutes,andthencoolthemixturetoroomtemperature.4. Inthefumehoodorunderasnorkel,add1goficeand1mLofconcentratedammonia,andmix.5. Allowthemixturetostandforafewminutes.Ifalayerseparates,removeitwithapipetandtestitusingtheferrichydroxamatetest(C-14)todetermineifanesterformed.Interpretation:Formationofanesterasindicatedbytheferrichydroxamatetest(C-14)indicatesapositiveresult.C-2AlkalineHydrolysisThisreactiontestsforthepresenceofamidesandesters.Ifyoususpectthatyouhaveanamide,useprocedureA.Ifyoususpectthatyouhaveanester,useprocedureB.(Notethatesterswithboilingpointshigherthan200°Cmaybeunreactive.)SafetyNotes:Sodiumhydroxideistoxicandcorrosive,causingseveredamagetoskin,eyes,andmucousmembranes.Wearglovesandavoidcontact.RecommendedControls:benzamideProcedureA:1. Place0.1goftheunknown(3dropsofaliquid)inatesttubecontaining4mLof6Msodiumhydroxide.2. Secureasmallpieceoffilterpaperoverthetopofthetubeandmoistenitwith2dropsof10%copper(II)sulfate.3. Boilthemixtureforaminuteortwoandnoteanycolorchangeonthefilterpaper.R

1 N O R 1 O O R 3 R 2 NaOH HN R 3 R 2 R 1 O O R 1 O O R 2 NaOH OH R 2 R 1 O O HCl R 1 OH O

Lab14:QualitativeOrganicAnalysis_____________________________________________________________________________________84. Acidifythesolutionwith6MHCI;ifacarboxylicacidprecipitates,saveitforuseasaderivative.Interpretation:Abluecoloronthefilterpaperindicatesanamide.Thisiscausedbythereactionofthefreeaminewiththecopper(II)sulfate.Someamideswillyieldaprecipitateoraseparateliquidphase(thecarboxylicacid)whenthehydrolysismixtureisacidified.Ifthetestisinconclusive,tryincreasingtheheatingtimeorrepeatingthereactionat200°Cusing20%KOHinglycerine.RecommendedControls:butylacetateProcedureB:1. Mix1mLoftheunknown(1gofasolid)with10mLof6Msodiumhydroxideinaroundbottomflask,andheatunderrefluxfor30minutes(oruntilthesolutionishomogeneous).2. Ifaseparateorganiclayerorresidueremains,heatthemixturelongeruntilitdisappearsoruntilitisapparentthatnoreactionistakingplace.(Mostestersboilingunder110°Cwillhydrolyzein30minutes;higher-boilingestersmaytakeseveralhours.)3. Coolthereactionmixture,removeanyorganiclayerifthereisone,andacidifytheaqueoussolutionwith6Msulfuric acid.Ifacarb oxylic acid precipitates,saveitforuse asaderivative.Interpretation:Evidenceforanesterisindicatedbydisappearanceoftheorganiclayer(ifany),andtheappearanceofaprecipitateuponacidification.C-3AluminumChloride&ChloroformThisreactiontestsforthepresenceofanaromaticring.Itcanonlybeusedforcompoundsthatdonotdissolveinsulfuricacid.SafetyNotes:Chloroformisharmfulifinhaledorabsorbedthroughtheskin,anditisasuspectedcarcinogeninhumans.Useglovesandhandleinthefumehoodorunderasnorkel.Aluminumchloridereactsviolentlywithwater,skinandeyecontactcancausepainfulburns,andinhalingthedustorvaporsisharmful.Usegloves,handleinthefumehoodorunderasnorkel,andkeepawayfromwater.RecommendedControls:toluene,biphenylProcedure:1. Inthefumehoodorunderasnorkel,prepareasolutioncontaining3dropsoftheunknown(or0.1gofasolid)in2mLofchloroform.Savethissolutionforstep4.2. Addabout0.2gofanhydrousaluminumchloridetoadrytesttubeandheatitoveraflame,anglingthetest tubesothatt heAlCl3sublimesontotheinne rwallofthetu beafewcentimetersabovethebottom.3. Allowthetubetocooluntilitcanbeheldcomfortablyinyourhand.ArH

CHCl 3 AlCl 3 C Ar Ar Ar

Lab14:QualitativeOrganicAnalysis_____________________________________________________________________________________94. Pipetafewdropsofthesolutionfromstep1downthesideofthetubesothatitcontactsthealuminumchloride.Noteanycolorchangeatthepointofcontact.Interpretation:Anintensecoloratthepointofcontactsuchasyellow-orange,red,blue,green,orpurpleindicatesthepresenceofanaromaticcompound.Alightyellowcolorisinconclusiveornegative.C-4BasicityTestThistestisusefulifyouhavealreadydeterminedthatyouhaveanamine.Itisusedtodistinguishalkylaminesfromaromaticamines.RecommendedControls:p-toluidine,dibutylamineProcedureforwater-solublecompounds:1. Dissolve4dropsofyourunknown(0.10gofasolid)in3mLofwater.2. MeasurethepHofthesolutionusingpHpaper.Procedureforwater-insolublecompounds:1. Dissolve4dropsofyourunknown(0.10gofasolid)in3mLofapH5.5acetate-aceticacidbuffer.2. Mixthoroughly.Interpretation:Water-solublealkylaminesg ivepHvaluesabove 11,whereaswater-solublearomaticamineshavepHvaluesbelow10.Water-insolublealkylaminesshoulddissolveinthebuffer,butwater-insolublearomaticamineswillnotdissolve.C-6Benedict'sTestThisreactiontestsforthepresenceofaldehydes.Notethatmostketonesandaromaticaldehydeswillnotreact.RecommendedControls:butanalProcedure:1. Add2dropsoftheunknown(80mgifitisasolid)to2mLofwater.2. Add2mLofBenedict'sreagent.3. Heatthemixturetoaboil.4. Observeifaprecipitateforms,andnoteitscolor.Interpretation:Benedict'sreagentcontainscopper(II)sulfate,sodiumcitrate,andsodiumcarbonate.Aldehydeswillreactwithth eCu2+fromthecopp er(II)sulfate toformcopper(I)oxidewhichappearsasayellowororangeprecipitate(itmaylookalittlegreeninthebluereactionsolution).Notethatmostketonesandaromaticaldehydeswillnotreact.RH

O ROH O Cu 2 O++ Cu 2+

Lab14:QualitativeOrganicAnalysis_____________________________________________________________________________________10C-8BromineWaterThisreactiontestsforthepresenceofphenolsandaromaticamines.RecommendedControl:phenolProcedure:1. Dissolve3dropsoftheunknown(0.1gofasolid)in10mLofwater.(Ifyouknowbasedontheresultsofyoursolubilityteststhattheunknownisinsolubleinwater,addethanoluntilyourunknownjustdissolves.)2. MeasurethepHofthesolutionwithpHpaper.3. Underthehood, addsaturat edbrominewaterd ropbydrop untilthebrominecolorpersists.Watchforevidenceofaprecipitate.Interpretation:Decolorizationofthebromine,accompaniedbysimultaneousformationofawhite(ornearlywhite)precipitate,indicatesaphenoloraromaticamine.Iftheunknownisaphenol,thepHoftheinitialsolutionshouldbelessthan7.C-9ChromicAcidThisreactiontestsforthepresenceofprimaryalcohols,secondaryalcohols,andaldehydes.SafetyNotes:Thechromicacidreagentiscorrosiveandcarcinogenic.Avoidcontact.RecommendedControls:1-butanol,butanalProcedure:1. Dissolve1dropoftheunknown(40mgofasolid)in1mLofreagentgradeacetone.OH

Br 2 (excess) OH Br Br Br NH 2 Br 2 (excess) NH 2 Br Br Br R OH ROH O CrO 3 acetone, H 2 SO 4 Cr 2 (SO 4 3 H 2 O R 1 OH R 1 R 2 O Cr 2 (SO 4 3 H 2 O R 2 CrO 3 acetone, H 2 SO 4 H O R OH O Cr 2 (SO 4 3 H 2 O R CrO 3 acetone, H 2 SO 4

Lab14:QualitativeOrganicAnalysis_____________________________________________________________________________________112. Add1dropofthechromicacidreagentandswirl.3. Notethetimeittakesfortheformationofacloudyblue-greensuspensiontooccur(thisshouldbeaccompaniedbythedisappearanceoftheorangecoloredreagent).Interpretation:Ar eactionwithin2-3s econdsindicatesap rimaryorsecondaryalcohol.W ithaliphaticaldehydes,thesolutionturnscloudyinabout5secondsandtheblue-greensuspensionformswithin30se conds.Aromatic aldehydes require30-90se condsorlongertoformth esuspension.Notethattheformationofanotherdarkcolor(particularlywiththecoloroftheliquidremainsorange)shouldbeconsideredanegativetest.C-112,4-DinitrophenylhydrazineThisreactiontestsforthepresenceofaldehydesandketones.SafetyNotes:2,4-Dinitrophenylhydrazine(DNPH)isharmfulifabsorbedthroughtheskin.Wearglovesandavoidcontact.RecommendedControls:cyclohexanone,benzaldehydeProcedure:1. Dissolve1dropoftheunknown(40mgofasolid)in1mLof95%ethanol(usemoreethanolifnecessarytocompletelydissolvetheunknown).2. Addthissolutionto2mLoftheDNPHreagent.3. Shakeandletthemixturestandfor15minutesoruntilaprecipitateforms.(Ifaprecipitateisobservedatthispoint,thisisconsideredapositiveresult.)4. Scratchtheinsideofthetesttubeandobserveifaprecipitateforms,andnoteitscolor.Interpretation:Formationofacrystallineyellowororange-redprecipitateindicatesanaldehydeorketone.Thecoloroftheprecipitatemaygiveacluetothestructureofthecarbonylcompound(unconjugatedaliphaticaldehydesandketonesusuallyyieldayellowprecipitate,whilearomaticandα,β-unsaturatedaldehydesandketonesyieldaorange-redprecipitate).C-12ElementalAnalysisThisreactiontestsforthepresenceofnitrogensandhalogens.SafetyNotes:Sodiumcancauseseriousburnsandthesodium-leadalloymayreactviolentlywithsomesubstances.Weargloves,avoidcontact,andkeepthesodium-leadalloyawayfromotherchemicals.RecommendedControls:butylamine,acetamide,bromobenzeneProcedure:R

1 R 2 O O 2 NNO 2 H N N O 2 NNO 2 H N NH 2 R 2 R 1

1. Inthefumehoodorunderasnorkel,place0.25gof10%sodium-leadalloyinasmall,drytesttubeheldverticallybyaclamp.2. MeltthealloywithaBunsenburnerflameandcontinueheatinguntilthesodiumvaporrisesabout1cmupthetube.3. UsingaPasteurpipet,add2dropsoftheunknown(or10mgofasolid)directlyontothemoltenalloysothatitdoesnottouchthesidesofthetube.4. Heatgentlytostartthereaction,removetheflameuntilthereactionsubsides,thenheatthetubestronglyforaminuteortwo,keepingthebottomadullredcolor.5. Letthetubecooltoroomtemperature.6. Dropwiseadd1.5mLofwaterandheatgentlyforaminuteorsountiltheexcesssodiumhasdecomposedandgasevolutionceases.7. FilterthesolutionthroughaPasteurpipetwithasmallplugofcotton,washthecottonwith1mLofwater,andcombinethewashwaterwiththefiltrate.(Usearubberbulbtoexpelanyliquidthatadherestothecotton.)Thefiltrateshouldbecolorlessorjustslightlyyellow.Ifitisdarker,repeatthefusionwithstrongerheatingormoreofthealloy.Totestfornitrogen:1. Put5dropsofthesodiumfusionsolutionintoasmalltesttube.2. Whilestirring,addenoughsolidsodiumbicarbonate,tosaturateit(alittleexcesssolidshouldbepresent).3. Add1drop ofth issolutionto atestt ubecontaining 10dropsofPNBreagent(p-nitrobenzaldehydeindimethylsulfoxide)andnoteanycolorchange.Totestforhalogens:1. Acidify10dropsofthesodiumfusionsolutionwithdilutenitricacid.2. Boilitgentlyunderthehoodforafewminutes.3. Addadroportwoof0.3Maqueoussilvernitrate,andnotethecolorandvolumeofanyprecipitatethatforms.(Ifavoluminousprecipitateforms,lettheprecipitatesettleandthenremovethesolventusingapipet.)4. Add2mLo f3M aqueous ammoniat othe solid ,shakevigorously,and noteyourobservations.5. Totestfurtherforbromineandiodine,acidify1mLoftheoriginalsodiumfusionsolutionwith1Msulfuricacid,boilforafewminutes,andadd0.5mLofdichloromethaneandathenadr opoffreshly prepare dchlorinewater.Shakean dlookforacolorinthedichloromethanelayer.Interpretation:InthePNBtest,apurplecolorindicatesthepresenceofnitrogen(greenindicatessulfur).Inthehalogentests,formationofavoluminousprecipitateonadditionofsilvernitrateindicatesthatahalogenispresent,andthecoloroftheprecipitate(asilverhalide)maysuggestwhichhalogen:whiteforchlorine,paleyellowforbromine,andyellowforiodine.Ifonlyafaintturbidityisproduced,itmaybecausedbytracesofimpuritiesorbyincompletesodiumfusion.If

Lab14:QualitativeOrganicAnalysis_____________________________________________________________________________________1 theprecipitateissilverchloride,itwilldissolveinaqueousammonia;silverbromideisonlyslightlysolubleandsilveriodideisinsoluble.Inthechlorinewatertest,ared-browncolorisproducedbyelementalbromineandavioletcolorbyelementaliodine.C-13FerricChlorideThisreactiontestsforthepresenceofphenols.RecommendedControl:phenolProcedure:1. Dissolve1dropoftheunknown(40mgofasolid)in1mLofwater.(Ifyouknowbasedontheresultsofyoursolubilityteststhattheunknownisinsolubleinwater,use0.5mLofwaterand0.5mLofmethanolinsteadof1mLofwater.)2. Addtwodropsof2.5%ferricchloridesolution.Interpretation:Formationofanintensered,green,blue,orpurplecolorsuggestsaphenoloraneasilyenolizablecompound(suchasanaldehydeorketone).Somephenolsdonotreactundertheseconditions.C-14FerricHydroxamateTestThisreactiontestsforthepresenceofesters.SafetyNotes:Hydroxylaminehydrochlorideistoxican dmutagenicanditcancauseaformofanemia.Avoidcontactwithitssolution.Sodiumhydroxideistoxicandcorrosive,causingseveredamagetoskin,eyes, andmucou smembranes. Wearglovesandavoidcon tactwith theNaOH solution.RecommendedControls:butylacetateProcedure:1. Beforeyouusetheferrichydroxamatetest,performthefollowingpreliminarytest.Dissolve1drop oftheunknown (40mgof asolid) in1mLof95% ethanol. Add1m Lof 1Mhydrochloricacid;thenaddtwodropsof2.5%ferricchloride.Ifadefinitecolorotherthanyellowresults, theferrichydroxamatetestcannot beused.T histesteliminatest hosephenolsandenolsthatgivecolorswithferricchlorideinacidicsolutionandthatwouldthereforegiveafalsepositiveresultintheferrichydroxamatetest.2. Mix1mLof0.5Methanolichydroxylaminehydrochloridewith5dropsof6Msodiumhydroxide.

Lab14:QualitativeOrganicAnalysis_____________________________________________________________________________________1 3. Add1dropoftheunknown(40mgofasolid)andheatthesolutiontoboiling.4. Allowittocoolslightlyandadd2mLof1Mhydrochloricacid.(Ifthesolutioniscloudyatthispoint,addenough95%ethanolmakeitclear.)5. Add5dropsof2.5%ferricchloridesolutionandobserveanycolorproduced.Ifthecolordoesnotpersist,addmoreferricchloridesolutiondropbydropuntilthecolorbecomespermanent.Interpretation:Aburgundyormagentacolorthatisdistinctlydifferentfromthecolorobtainedinthepreliminarytestindicatesanester.C-15Hinsberg'sTestThistestisusefulifyouhavealreadyestablishedthatyouhaveanamine.Itisusefulforclassifyingaminesasprimary,secondary,ortertiary.Itisimportanttorecordallobservationscarefullyduringthistest.SafetyNotes:p-Toluenesulfonylchlorideistoxicandcorrosive.Useglovesandworkinafumehoodorunderasnorkel.RecommendedControls:butylamine,dibutylamine,tributylamineProcedure:1. Inthefumehoodorunderasnorkel,mix3dropsoftheunknown(0.1gofasolid)with5mLof3Msodiumhydroxideinatesttube.2. Add0.2gofp-toluenesulfonylchloride.3. Stopperthetubeandshakeitintermittentlyfor3-5minutes.4. Removethestopperandwarmthesolutioninahotwaterbath,withshaking,for1minute.5. UsepHpapertocheckifthesolutionisbasic(ifitisnotbasic,addmoreNaOHuntilitis).6. Ifthereisasolidorliquidresidueinthetesttube,separateitfromthesolutionbyvacuumfiltration(ifitisasolid)orwithaPasteurpipet(ifitisaliquid).S

O O Cl R NH 2 S O O N R S O O N R H NaOH HCl soluble insoluble S O O Cl R 1 H N S O O N R 2 NaOH insoluble R 2 R 1 HCl S O O N R 2 insoluble R 1 S O O Cl R 1 N NaOH insoluble R 2 HCl soluble R 3 R 1 N R 2 R 3 S O O O R 1 N R 2 R 3 H

Lab14:QualitativeOrganicAnalysis_____________________________________________________________________________________157. Testthesolubilityofthesolidorliqui dresiduei nwaterand( ifit'sinsolubl e)in 5%hydrochloricacid.8. Acidifytheoriginals olutionwit h6Mhydrochloricacidand ,ifnoprecipitateforms immediately,scratchthesidesofthetesttubeandcool.Interpretation:Formationofawhitepre cipitat e( ap-toluenesulfonamide)whenthereactionmixtureisacidifiedindicatesaprimaryamine.Mostprimaryaminesyieldaclearsolutionaftertheinitialreaction,butsomeformsodiumsaltsordisulfonylderivativesthatprecipitateduringthereaction.Thesaltsshoulddissolveinwater,andaminesthatformdisulfonylderivativesshouldyieldadditionalprecipitatewhenthereactionmixtureisacidified.Mostsecondaryaminesyieldawhitesolidthatdoesnotdissolveinwateror5%HCl.Aliquidresiduethatismored ensethanwater andin solublein5% HCImaybea secondaryamine's arenesulfonamidethathasfailedtocrystallize.Tertiaryaminesshouldnotreact;anyresiduewillbetheoriginalliquidorsolidamine,whichshoulddissolveindiluteHCI.Water-solubletertiaryaminesyieldaclearsolutionthatdoesnotformaseparatephaseonacidification.C-16IodoformTestThistestisusefulifyouhavealreadyestablishedthatyouhaveanalcoholoraketone.Itindicatesifyouhave-CH(OH)CH3and-COCH3groupings.RecommendedControls:2-butanol,2-butanoneProcedure:1. Dissolve3dropsoftheunknown(or0.1gofasolid)in2mLofwater.(Ifyouknowbasedontheresultsofyoursolubilityteststhattheunknownisinsolubleinwater,usemethanolasasolventinsteadofwater.)2. Add1mLof3Msodiumhydroxidesolution.3. Addthe0.5Miodine-potassiumiodidereagentdropbydropuntilthebrowniodinecolorpersistsaftershaking.(Ifayellowprecipitateisobservedatthispoint,thisisconsideredapositiveresult.)4. Placethetesttubeina60°Cwaterbathandaddmoreiodine-potassiumiodidesolutionasnecessaryuntilthebrowncolorremainsafter2minutesofheating.5. Add3MNaOHdropbydropuntilthebrowncolorjustdisappears(alightyellowcolormayremain).6. Removethetesttubefromthewaterbath,add10mLofcoldwater,andletitstandfor15minutes.CH

3 OH R CI 3 O R NaOH I 2 RO O CHI 3 CH 3 O RCI 3 O R NaOH I 2 R O O CHI 3

Lab14:QualitativeOrganicAnalysis_____________________________________________________________________________________16Interpretation:Formationofayellowprecipitate(iodoform)indicatesapositivetest.Ifyouwishtoconfirmtheidentityoftheprecipitate,measureitsmeltingpoint(121°C).Thetestispositiveformethylketonesandacetaldehyde,andforalcoholsthatcontaina-CH(OH)CH3grouping.C-17Lucas'sTestThistestisusefulifyouhavealreadyestablishedthatyouhaveanalcohol.Itisusefulforclassifyingalcoholsasprimary,secondary,ortertiary.However,notethatthistestcannotbeusedforsolidalcoholsoralcoholsthatarenotsolubleintheLucasreagent(typicallyalcoholsthathaveboilingpointshigherthan~140°C).SafetyNotes:TheLucasreagent(ZnCl2inconcentratedHCI)cancauseseriousburns,andisharmfulifinhaled.Useglovesandhandleinafumehoodorunderasnorkel.RecommendedControls:1-butanol,2-butanol,2-methyl-2-propanolProcedure:1. Inthefumehoodorunderasnorkel,add2mLoftheLucasreagenttoatesttube.2. Add4dropsoftheunknown,thenstopperthetubeimmediately,andshakevigorously.3. Allowthemixturetostandfor15minutesormore,observingitperiodicallyforevidenceofreaction(cloudinessorlayerseparation).Ifthealcoholappearstobesecondaryortertiary,repeatthetestusingconcentratedHClinplaceoftheLucasreagent.Interpretation:Tertiaryalcoholsthata resolubleintheLucasreagent shouldturnther eagentcloudyalmostimmediatelyandquicklyformaseparatelayerofalkylchloride.Secondaryalcoholsusuallyturntheclearsolutioncloudyin3-5minutesandformadistinctlayerwithin15minutes.Primaryalcoholsdonotreactundertheseconditions.(Mostallylicandbenzylicalcoholsgivethesameresultastertiaryalcohols,exceptthatthechlorideformedfromallylalcoholisitselfsolubleinthereagen tandseparatesoutonl yuponadditi onoficewater.)High-boilingalcoholsth atareinsolubleintheLucasreagentcannotbetestedbecausetheywillformaseparatelayerimmediately.WhentestedwithconcentratedHCI,atertiaryalcoholshouldreactwithinminutes,andasecondaryalcoholshouldnotreactatall.C-18NeutralizationEquivalentThistestisusefulifyouhavealreadyestablishedthatyouhaveacarboxylicacid.Itisusefulforprovidinginformationaboutthemolecularweightofyourunknownandthenumberofcarboxylicacidspresentinyourunknown.RecommendedControl:adipicacidProcedure:ROH

HCl ZnCl 2 RCl (Soluble)(Insoluble) R OH O R O O NaOH

Lab14:QualitativeOrganicAnalysis_____________________________________________________________________________________171. Accuratelyweigh(to3decimal places)ab out0.2gofan unknowncar boxylicacidanddissolveitin50-100mL ofwate r,et hanol,oramixtureofthetwo,depen dingonitssolubility.2. Titratethissolutionw ithastan dardize dsolutionof0.1Msodi umhydrox ideusingphenolphthaleinastheindicator(orbromothymolblueifthesolventisethanol).3. Calculatetheneutralizationequivalent(NE)oftheacidusingtheformulashown.Interpretation:Theneutralizationequivalent(equivalentweight)ofacarboxylicacidisequaltoitsmolecularweightdividedbythenumberofcarboxylacidsithas.Forinstance,theNEofadipicacid[HOOC(CH2)4COOH;MW=146] is73.A solidcarb oxylic acidt hathasan unusuall ylowneutralizationequivalentforitsmeltingpointprobablycontainsmorethanonecarboxylicacid.C-20QuinhydroneThistestisusefulifyouhavealreadyestablishedthatyouhaveanamine.Itisusefulforclassifyingaminesasprimary,secondary,ortertiary.Notethathistestwillnotworkfordiaminobenzenesornitro-substitutedaromaticamines.ThistestshouldberuninconjunctionwithtestC-4orwithaninfraredspectrumthatshowswhethertheamineisaliphaticoraromatic.Controlsshouldberunforcomparisonsincethecolorsaredifficulttoidentify.SafetyNotes:Thecomponentsofquinhydrone(hydroquinoneandbenzoquinone)aretoxicandirritating.Avoidcontactwiththereagent.RecommendedControls:butylamine,dibutylamine,tributyla mine,aniline,N-methylaniline,N,N-dimethylanilineProcedure:1. Shake1dropofanunknownalkylamine(30mgofasolid)or6dropsofanunknownarylamine(0.2gofasolid)with6mLofwaterinatesttube.Iftheaminedissolves,add6mLmoreofwater;ifnot,add6mLofethanol.2. Shakethemixture,add1dropof2.5%quinhydroneinmethanolandletitstandfor2minutesormore.3. Comparethecolorofthissolutionwiththoseofthecontrols.Interpretation:Mostaminesfromthefollowingclassesgivethecolorsindicated.ItisbesttousethistestinconjunctionwithHinsberg'stestoranIRspectrumforconfirmation.Amine Type 1° 2° 3° Aliphatic violet rose yellow Aromatic rose amber yellow C-23Tollen'sTestThisreactiontestsforthepresenceofaldehydes.NE =

mass of sample in mg mL of NaOH X molarity of NaOH

Lab14:QualitativeOrganicAnalysis_____________________________________________________________________________________18SafetyNotes:Silvernitrateiscorrosiveandtoxic.Wearglovesandavoidcontact.UsethereagentimmediatelyafterpreparationandbesuretodisposeoftheTollen'sreagentasindicated(explosivesilversaltsmayformifTollen'sreagentisstoredorimproperlydisposedof).RecommendedControls:benzaldehydeProcedure:1. Measure2mLof0.3Maqueoussilvernitrateintoatesttubeandadd1dropof3Msodiumhydroxide.2. Add2Maqueousammoniadropbydrop,withshaking,untiltheprecipitateofsilveroxidejustdissolves(avoidanexcessofammonia).3. Add1dropoftheunknown(40mgofasolid)tothissolution,shakethemixture,andletitstandfor10min utes.(If asilvermi rrorisobservedatthispoint ,thisisconsi dereda positiveresult.)4. Heatthemixtureina35°Cwaterbathfor5minutes.5. Immediatelyafterthetesthasbeencompleted,dissolveanysolidresiduein1Mnitricacidandthendisposeofthesolutioninthedesignatedwastecontainer.6. Interpretation:Formationofasilvermirrorontheinsideofthetesttubeisapositivetestforanaldehyde.(Notethatifthetubeisnotsufficientlyclean,ablackprecipitateorasuspensionofmetallicsilvermayforminstead.)DerivativesofAlcoholsD-1p-Nitrobenzoatesand3,5-DinitrobenzoatesForthesederivatives,itisextremelyimportanttoensurethatyourglasswareandyouralcoholaredry(i.e.,freeofwater).Watercaneasilyreactwiththeacidchloridestoformcarboxylicacidstoformtherespectivecarboxylicacidsratherthanthedesiredesters.(Note:Thep-nitrobenzoicacidhasameltingpointof237°C.andthe3,5-dinitrobenzoicacidhasameltingpointof205-207°C.)Ifnecessary,dryyourglasswareinanovenbeforeproceeding.H

O R O O Ag R Ag(NH 3 2 OH

Lab14:QualitativeOrganicAnalysis_____________________________________________________________________________________19SafetyNotes:Acidchloridesarecorrosiveandlachrymators.Avoidcontactwiththesereagentsanduseinafumehoodorunderasnorkel.Procedure:1. Dryyourunknownalcoholwithmagnesiumsulfateorsodiumsulfate.2. Filtertoremovethedryingagent.3. Ifyouaremakingthep-nitrobenzoatederivative,add0.20gofp-nitrobenzoylchloridetoasmallroundbottomflask.Ifyouaremakingthe3,5-dinitrobenzoatederivative,add0.20gof3,5-dinitrobenzoylchloridetoasmallroundbottomflask.4. Inthefumehoodorunderasnorkel,dropwiseadd0.10gofyourunknownalcoholtotheacidchloridewhilestirring.5. Heatthemixtureina60-70°Cwaterbath.Ifyouralcoholhasboilingpointof<160°C,heatthemixturefor5minutes.Ifyouralcoholhasboilingpointof>160°C,heatthemixturefor15minutes.6. Stirin4mLof0.2Msodiumcarbonate.7. Heatthemixtureto50-60°Cfor30seconds.8. Cooltoroomtemperatureandtheninanicebath.9. Collecttheprecipitatebysmall-scalevacuumfiltration.Washwithcoldwater.10. Recrystallizetheprecipitatefromethanoloranethanol-watermixture.D-2Phenylurethanesand1-NaphthylurethanesForthesederivatives,itisextremelyimportanttoensurethatyourglasswareandyouralcoholaredry(i.e.,freeofwater).Watercaneasilyreactwiththeisocyanatestoformtherespectiveureasratherthanthedesiredcarbamates.(Note:Thedipheylureahasameltingpointof241°C,andthedi-1-naphthylureahasameltingpointof297°C.)Ifnecessary,dryyourglasswareinanovenbeforeproceeding.SafetyNotes:Isocyanatesareirritantsandlachrymators.Avoidcontactwiththesereagentsanduseinafumehoodorunderasnorkel.Procedure:1. Dryyourunknownalcoholwithmagnesiumsulfateorsodiumsulfate.

02. Filtertoremovethedryingagent.3. Ifyouaremakingthephenylurethanederivative,add5dropsofphenylisocyanatetoasmallroundbottomflask.Ifyouaremakingthe1-naphthylurethanederivative,add5dropsof1-naphthylisocyanatetosmallroundbottomflask.4. Inthef umehood orunderasno rkel,dropwise add5drops ofth edryalcoholtothe isocyanate.Ifnoreactionisapparent,heatthemixtureina60-70°Cwaterbathfor15minutes.5. Cooltoroomtemperatureandtheninanicebath.6. Collecttheprecipitatebysmall-scalevacuumfiltration.7. Recrystallizetheprecipitatefrompetroleumetherorheptane.(Ifnecessary,performahotgravityfiltration.)DerivativesofAldehydesandKetonesD-32,4-DinitrophenylhydrazonesSafetyNotes:2,4-Dinitrophenylhydrazineistoxicandsulfuricacidiscorrosive.Avoidcontactwiththesereagentsanduseinafumehoodorunderasnorkel.Procedure:1. Inasmallroundbottomflask,dissolve0.10goftheunknownaldehydeorketonein1mLofethanol.(Ifyourunknownisnotcompletelydissolved,addethanoldropbydropuntilitgoesintosolution).2. Inthefumehoodorunderasnorkel,dropwiseadd3mLofthe2,4-dinitrophenylhydrazine-sulfuricacidreagent.3. Allowthesolutiontostandatroomtemperatureuntilcrystallizationiscomplete.Ifnocrystalsform,heatthemixtureina60-70°Cwaterbathfor15minutes,andthenitcoolagain.Ifthere isstil lnoprecipitate,add coldwate rdropbydroptothe solution untilprecipitateisobserved.4. Collecttheprecipitatebysmall-scalevacuumfiltration.Washoncewith5mLofcold5%NaHCO3andoncewithcoldwater.5. Recrystallizetheprecipitatefromethanoloranethanol-watermixture.(Note:Ifmorethan6mLofethanolisneededforrecrystallization,addethylacetatedropbydroptothehotsolutionuntileverythingisdissolved.)

1D-4SemicarbazonesSafetyNotes:Semicarbazidehydrochlorideisasuspec tedcarcinogen.Avoidcontactwiththe reagent.Procedure:1. Mixtogether0.20gofsemicarbazidehydrochloride,0.30gofsodiumacetate,and2mLofwaterinasmallroundbottomflask.2. Ifyourunknownaldehydeorketoneiswatersoluble,add0.20gofitdirectlytotheflaskandstir todissolve.Ifyour unknow naldehydeorketoneisnot watersolub le,adda minimumamountofethanoltothemixtureuntilyourunknowngoesintosolution.3. Stirthemixturefortwominutes.4. Coolthemixtureinanicebath.Ifnocrystalsform,heatthemixtureina60-70°Cwaterbathfor5minutes,andthenitcoolagain.5. Collecttheprecipitatebysmall-scalevacuumfiltration.Washwithcoldwater.6. Recrystallizetheprecipitatefromethanoloranethanol-watermixture.D-5OximesSafetyNotes:Hydroxylaminehydrochlorideistoxicandmutagenic.Avoidcontactwiththereagent.Procedure:1. Mixtogether0.125gofhydroxylaminehydrochloride,0.30gofsodiumacetate,and2mLofwatertoasmallroundbottomflask.2. Ifyourunknownaldehydeorketoneiswatersoluble,add0.20gofitdirectlytotheflaskandstirt odissolve.Ifyour unknow naldehydeorketoneisnotw atersoluble,addaminimumamountofethanoltothemixtureuntilyourunknowngoesintosolution.3. Stirthemixturefortwominutes.4. Coolthemixtureinanicebath.Ifnocrystalsform,heatthemixtureina60-70°Cwaterbathfor15minutes,andthenitcoolagain.Ifthereisstillnoprecipitate,addcoldwaterdropbydroptothesolutionuntilprecipitateisobserved.5. Collecttheprecipitatebysmall-scalevacuumfiltration.Washwithcoldwater.6. Recrystallizetheprecipitatefromethanoloranethanol-watermixture.

ReportingYourResultsWriteyourreportaccordingtotheguidelinesdescribedin-Topic4:WritinganOrganicChemistryLabReport-.Workbyyourselfonthisreport.References&AdditionalResources1. Lehman,J.W.OperationalOrganicChemistry:AProblem-SolvingApproachtotheLaboratoryCourse,3rded.;PrenticeHall:UpperSaddleRiver,NJ,1999;pp529-572.

Table 1. Possible Alcohol Unknowns Alcohol BP (°C) 3,5-Dinitro benzoate MP (°C) 4-Nitro benzoate MP (°C) 1-Naphthyl urethane MP (°C) Phenyl urethane MP (°C) methanol 65 108 96 124 47 ethanol 78 93 57 79 52 2-propanol 83 123 110 106 88 2-methyl-2-propanol 83 142 - - 136 2-propen-1-ol 97 49 28 108 70 1-propanol 97 74 35 105 57 2-butanol 99 76 26 97 65 2-methyl-2-butanol 101 116 85 72 42 2-methyl-1-propanol 108 87 69 104 86 3-pentanol 116 101 17 95 48 1-butanol 118 64 36 71 61 2-pentanol 119 62 24 74 - 3-methyl-3-pentanol 123 94 (62) 69 104 43 3-methyl-1-butanol 132 61 21 68 57 4-methyl-2-pentanol 132 65 26 88 143 1-pentanol 137 46 11 68 46 cyclopentanol 141 115 62 118 132 2-ethyl-1-butanol 148 51 - 60 - 1-hexanol 157 58 5 59 42 cyclohexanol 161 113 50 129 82 furfuryl alcohol 172 80 76 130 45 1-heptanol 177 47 10 62 60 2-octanol 174 32 28 63 114 1-octanol 195 61 12 67 74 1-phenylethanol 202 95 43 106 92 benzyl alcohol 204 113 85 134 77 2-phenylethanol 219 108 62 119 78 1-decanol 231 57 30 73 60 3-phenyl-1-propanol 236 45 47 - 92 1-dodecanol 259 60 45 (42) 80 74 *A dash indicates that no information is reported in the literature **Melting points in parenthesis represent conflicting literature values

Table 2. Possible Aldehyde Unknowns Aldehyde BP (°C) MP (°C) 2,4-Dinitro phenylhydrazone MP (°C) Semicarbazone MP (°C) Oxime MP (°C) ethanal 21 168 (157) 162 47 propanal 48 148 (155) 154 40 propenal 52 165 171 - 2-methylpropanal 64 187 (183) 125 (119) - butanal 75 123 106 - 3-methylbutanal 92 123 107 48 pentanal 103 106 (98) - 52 2-butenal 104 190 199 119 2-ethylbutanal 117 95 (30) 99 - hexanal 130 104 106 51 heptanal 153 106 109 57 2-furaldehyde 162 212 (230) 202 91 2-ethylhexanal 163 114 (120) 254d - octanal 171 106 101 60 benzaldehyde 178 239 222 35 phenylethanal 195 33 121 (110) 153 (156) 99 4-methylbenzaldehyde 204 234 234 (215) 80 3,7-dimethyl-6-octenal 207 77 84 (91) - 2-chlorobenzaldehyde 209 213 (209) 229 (146) 76 (101) 4-methoxybenzaldehyde 248 253d 210 133 2-methoxybenzaldehyde 38 254 215 92 4-chlorobenzaldehyde 48 265 230 110 (146) 3-nitrobenzaldehyde 58 290 246 120 4-nitrobenzaldehyde 106 320 221 (211) 133 (182) *A dash indicates that no information is reported in the literature **Melting points in parenthesis represent conflicting literature values ***If the substance changes color and smokes, this is considered decomposition (d = decomposes)

5Table 3. Possible Ketone Unknowns Ketone BP (°C) MP (°C) 2,4-Dinitro phenylhydrazone MP (°C) Semicarbazone MP (°C) Oxime MP (°C) acetone 56 126 187 59 2-butanone 80 118 146 - 3-methyl-2-butanone 94 124 113 - 2-pentanone 101 143 112 (106) 58 3-pentanone 102 156 138 69 3,3-dimethyl-2-butanone 106 125 157 75 (79) 4-methyl-2-pentanone 117 95 (81) 132 58 2,4-dimethyl-3-pentanone 124 95 (88) 160 34 2-hexanone 128 110 125 49 4-methyl-3-penten-2-one 130 205 164 (133) 48 cyclopentanone 131 146 210 (203) 56 4-heptanone 144 75 132 - 2-heptanone 151 89 123 - cyclohexanone 156 162 166 91 2,6-dimethyl-4-heptanone 168 92 122 210 2-octanone 173 58 124 - cycloheptanone 181 148 163 23 acetophenone 202 20 238 198 (203) 60 2-methylacetophenone 214 159 205 61 propiophenone 218 21 191 182 (174) 54 3-methylacetophenone 220 207 203 57 4-methylacetophenone 226 28 258 205 88 2-undecanone 228 63 122 44 4-phenyl-2-butanone 235 127 142 87 3-methoxyacetophenone 240 - 196 - 2-methoxyacetophenone 245 - 183 83 (96) 4-methoxyacetophenone 38 228 198 87 4-phenyl-3-buten-2-one 42 227 (223) 187 117 benzophenone 48 238 167 144 2-acetonaphthone 54 262d 235 145 3-nitroacetophenone 80 228 257 132 9-fluorenone 83 283 234 195 *A dash indicates that no information is reported in the literature **Melting points in parenthesis represent conflicting literature values ***If the substance changes color and smokes, this is considered decomposition (d = decomposes

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