CHEM 3332 Lecture 21Outline of Last Lecture VI Aldehyde and Keytone SynthesisA. Oxidation of AlcoholsB. Cleavage of Alekens by OnzolysisC. Friedel-Crafts AcylationD. Hydrogenation of AlkynesE. 1,3-Dithiane Synthesis of Aldehydes and KetonesA multi-step synthesis:Example: F. Ketones from Carboxylic Acids1.2.3.Ex:G. Ketones from NitrilesEx:H. Aldehydes and Keytones from Acid Chlorides1. Reduction to aldehydesMechanisma) A milder reagent: lithium aluminum tri(t-butoxy)hydrideb) The rosenmunf ReductionEx:2. Conversion to ketones with litium dialkylcuprates (Gilman reagent)Ex:A reminder: use grilman reagent in the corey-House reaction:VII. Reactions of Aldehydes and KeytonesA. Alpha-Carbon reactions – covered in Ch 22B. Nucleophilic Addition Reactions1. Grignard Reaction:2. Addition of Acetylide3. Addition of Hydride4. Catalytic hydrogenation:similar to hydrogenation of alkenes, but aldehydes and keytones are less reactiveOutline of Current Lecture III. Direct Amide Synthesis IV. Reduction of RCO2HA. (Review) LAH reduction – not selectiveThese 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.B. Diborane reduction – very selective!- CO2H reacts faster with B2H6 than any other functional groupC. (Review) Reduction to aldehydesV. Ketone Formation (Review)VI. Decarboxylation – The Hunsdiecker Reaction – converts heavy metal salts of RCO2H into alkyl halides with 1 less carbonMechanism: first-carboxylic acid salt is formed with metal then:Spectroscopy SummaryCurrent
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