Show how you would transform pentanoic acid to

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Show how you would transform pentanoic acid to
3-heptanone. You may use any additional
reagents that are needed.
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Synthesis Review

• Oxidation
• 2? alcohol Na2Cr2O7 ? ketone
• 1? alcohol PCC ? aldehyde
• Ozonolysis of alkenes.

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Synthesis Review (2)

• Friedel-Crafts acylation
• Acid chloride/AlCl3 benzene ? ketone
• CO HCl AlCl3/CuCl benzene ? benzaldehyde
  (Gatterman-Koch Formylation)
• Hydration of terminal alkyne
• Use HgSO4, H2SO4, H2O for methyl ketone
  (markovnikov)
• Use Sia2BH followed by H2O2 in NaOH for aldehyde.
  (anti-markovnikov)

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Synthesis Using 1,3-Dithiane

• Remove H with n-butyllithium.

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Ketones from 1,3-Dithiane

• After the first alkylation, remove the second H,
  react with another primary alkyl halide, then
  hydrolyze.

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Ketones from Carboxylates

• Organolithium compounds attack the carboxyl and
  form a dianion.
• Neutralization with aqueous acid produces an
  unstable hydrate that loses water to form a
  ketone.

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Ketones from Nitriles

• A Grignard or organolithium reagent attacks the
  nitrile carbon.
• The imine salt is then hydrolyzed to form a
  ketone.

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Aldehydes from Acid Chlorides

• Use a mild reducing agent to prevent reduction to
  primary alcohol.

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Ketones from Acid Chlorides

• Use lithium dialkylcuprate (R2CuLi) (Gilman
  Reagent), formed by the reaction of 2 moles of
  R-Li with cuprous iodide.

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What reagents can be used to convert 1-hexyne
into 2-hexanone? a) 1. Sia2BH 2. H2O2, NaOH b)
HgCl2, H2SO4, H2O c) 1. O3 2. (CH3)2S d) 1.
CH3MgBr 2. CO2 e) 1. H2, Ni 2. Na2Cr2O7, H2SO4
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How would you synthesize (R)-()-6-benzyloxy-4-me
thyl-1-phenyl-1-hexanone from (R)-()-citronellol?

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Lets work backwards . . .
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Total Synthesis
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