Chem 334 1st Edition Lecture 10Outline of Last Lecture I. Nomenclature of aldehydes and ketonesOutline of Current Lecture II. Ring Aldehydes and KetonesIII. Synthesis of AldehydesIV. Synthesis of KetonesV. Reactivity of Aldehydes and KetonesCurrent LectureRing aldehydes and ketones:When naming an aldehyde ring, name the ring first and then add carboxaldehyde OCyclopentane carboxaldehydeWhen naming a ketone ring, add –one to the end of the name of the ring. OCyclohenanoneSynthesis of Aldehydes:A. Oxidation of primary alcohols OH PCC OR R HB. Ozonolysis O3 O OThese notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.Me2S H H In ozonolysis, O3 cleaves the double bond and makes two identical aldehydesC. Reduction of Acid Chlorides: This is a two step reaction. First we add the reducing agent, then weadd water. This reaction MUST be done at -78⁰C O SOCl2 O 1. LiAlH(OtBu)3 O R OH R Cl 2. H2O R HD. Ester Reductions:Disobutylaluminum hydride (DIBAL-H) is a very sterically hindered reducing agent. This means that it is much less reactive than LiAlH4 O 1. DiBal OR OR 2. H2O R H HOR- O DiBal O O H2O H OHE. Nitrile Reductions: DIBAL-H O H2O R HF. Hydroboration of Terminal Alkynes: HB(Sia)2OH2O2, NaOH R HSynthesis of Ketones:A. Oxidation of secondary alcohols OH H2CrO4 OR – ≡R – ≡NB. Ozonolysis of alkenes O3 O O Me2S C. Friedal Crafts Acylation O O AlCl3 ClD. Hydroboration of Symmetrical alkynes: BH3 OH2O2, NaOHE. Nitrile reacted with an organometallic: MgBr O H3O R F. Oxymercuration of Terminal Alkynes or Symmetrical Alkynes: This essentially results in a Markovnikov addition Hg(OAc)2, H2SO4O R Reactivity of Aldehydes and Ketones:Aldehydes are more reactive than ketones due to sterics and electronics. Sterics: Aldehydes always have a small H attached to the carbonyl, while ketones always have something larger attached to the carbonyl. Because the ketone has more sterics, it is harder for the nucleophile to attack. R – ≡R – ≡NElectronics: Alkyl groups are electron donating. The nucleophile attacks the electrophilic position. The ketone carbon is less electrophilic than the aldehyde carbon. This means that if we have an aldehyde anda ketone in a reaction, we know to react with the
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