solutions to problems aldehydes and ketones, building bridges to knowledge

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SolutionstoProblemsAldehydesandKetones

BuildingBridgestoKnowledge

PhotooftheHuanpuRiverCruiseBoat’sgangplankinShanghai,China1. SuggestIUPACnamesforthefollowingmolecules.

(a)

6-phenyl-3-hexanone

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(b)

7-phenyl-4-oxohexanal (c)

5,7-diphenylheptanal2. Suggestamechanismforthefollowingconversion.

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(1)

(2)

(3)

(4)

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(5)

3. Suggesttheproductexpectedfromthereactionofbenzaldehydewitheachofthe

following.

(a)

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(b) dilutesodiumhydroxide

Noreaction

(c) concentratedsodiumhydroxide

(d) propanalanddilutehydroxide

(e) butanalanddilutesodiumhydroxide

(f)

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4. Suggestasynthesisforthefollowingmoleculefromtheindicatedstarting

materialandanynecessaryorganicandinorganicmaterials.

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5. Writeamechanismforyoursynthesisoftheesterinproblem4.(1)

(2)

6. Using1-propanolastheonlysourceoforganiccompoundsandanyother

necessaryinorganicreagents,suggestsynthesesforthefollowing.

(a)

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9

(b)

7. Suggestasynthesisforthefollowingmoleculefromtheindicatedorganic

compoundandanyotheravailableinorganicmaterials.

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8. Suggestasynthesisforthefollowingfromtheindicatedstartingmaterialand

anynecessaryinorganicandorganiccompounds.

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9. CompoundIexhibitsthefollowingprotonmagneticresonancespectrum.10.

1HNMRofcompoundI

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AconstitutionalisomerofcompoundI,compoundII,exhibitsthe followingprotonmagneticspectrum.

1HNMRofcompoundII WhencompoundIwastreatedwithlithiumaluminumhydride followedbyhydrolysis,thenaqueousacidatabout200oC, compoundIII,C10H12wasproduced.CompoundIIIhastwo isomers.

FollowingistheprotonmagneticresonancespectrumofcompoundIII,C10H12

1HNMRofcompoundIIIWhencompoundIIwastreatedwithlithiumaluminumhydridefollowedbyhydrolysis,thenaqueousacidatabout200oC,compoundIV,C10H12wasproduced.FollowingistheprotonmagneticresonancespectrumofcompoundIV,C10H12.

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CompoundIVhasoneisomer.CompoundsIIIandIVarealsoconstitutionalisomers.ThestructureofcompoundIis

ThestructureofcompoundIIis

CompoundIIImayhaveacisconfigurationoratransconfiguration.Thesestructuresare

CompoundIVdoesnothaveanonsuperposable/nonsuperimposablemirrorimage.

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1HNMRofcompoundIV 10. Acertainbiologicallyactiveterpene,C10H16Ofollowstheisoprenerulewillform

anoxime,asemicarbozide,anda2,4-dintrophenylhyradazide.Uponozonolysis,theterpenesproducesthefollowingcompounds

Suggestastructureconsistentwiththeexperimentaldataandtheisoprene rule.

11. Aterpenethatfollowstheisopreneruledecolorizesadilutesolutionof

potassiumpermanganate,and,upon,treatmentwithhotconcentratedpotassiumpermanganateinsulfuricacid,producesthefollowingtwoorganicacidsacids:

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Suggestastructurefortheterpenethatisconsistentwiththe experimentalevidence.

12. Suggestasynthesisforthefollowingconversionusingappropriateinorganic

reagents.

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13. Suggestaseriesofelementarystepsthatwouldrationalizethefollowing

observations.

(a)

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(b)

(1)

(2)

(3)

14. Predicttheproductorproductsexpectedinthefollowingsequenceofreactions.

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15. CompoundIistreatedwiththereagentsoftheClemmensenreductionto

producecompoundII.TreatingcompoundIIwiththereagentsforhydroboration-oxidationproducescompoundIII.CompoundIIIupontreatmentwithpyridiniumchlorochromateproducescompoundIV.

CompoundI ClemmensenReduction:

compoundII

Hydroboration-Oxidation:

compoundIII

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OxidationwithPyridiniumChlorchromate

compoundIV16.Considerthefollowingsynthesispathway:

C9H16O4 + LiAlH4H2O

C9H18O3

C9H18O3H3O

+C6H12O2

C6H10O2C6H12O2 + PDC

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17.Treatingcompound17A,C6H12O,withiodineinsodiumhydroxide,resultsintheformationayellowprecipitateandcompound17B,C5H9O2Na.Acidificationofcompound17BformedC5H10O2,compound17C.Treatingcompound17CwithLiAlH4followedbyhydrolysisproducescompound17D.Theinfraredspectrumofcompound17Dexhibitedaprominentstretchingtransmittancesignalat3333cm-1.Followingaretheprotonmagneticresonancespectrumandcarbon-13magneticresonancespectrumofcompound17D.1HNMRCompound17D

13CNMRCompound17D

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Sulfuricacidconvertedcompound17Dtocompound17E.Ozonolysisofcompound17Egavecompound17Fand17G.Prominentmassspectrumpeaksforcompound17Foccuratm/e29and43.Prominentmassspectrumpeaksforcompound17Goccuratm/e43and58.Usethesedatatodeterminethestructuresofcompounds17A,17B,17C,17D,17E,17F,and17G.Pleasesupportyouranswerswithchemicalequationsandanygivenspectradata.Provideadetailedmechanismfortheconversionof17Dto17Ewithsulfuricacid.

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Mechanismof17Dto17E: (1)

17D (2)

(3)

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(4)

17E