Addition of Organometallic Reagents to Carbonyl Compounds

The product of this nucleophilic attack is an alkoxide ion, a strong base. Addition of water or a dilute acid protonates the alkoxide to give the alcohol. 

The electrostatic potential map (EPM) of formaldehyde shows the polarization of the carbonyl group, with an electron-rich (red) region around oxygen and an electron-poor (blue) region near carbon. 

Grignaril and organolithium reagents provide some of the best methods for assembling a carbon skeleton. These strong nucleophiles add to ketones and aldehydes to give alkoxide ions, which are proton ated to give alcohols. 

Formation of the Grignard reagent Magnesium reacts with an alkyl halide in an ether solution. 

Reaction 1 The Giignard reagent attacks a carbonyl compound to form an alkoxide salt. 

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There is another possible mechanism for addition of organometallic reagents to carbonyl compounds. This involves a discrete electron-transfer step. °... 

Enantioselective Addition of Organometallic Reagents to Carbonyl Compounds Chirality Transfer, Multiplication, and Amplification 255... 

ENANTIOSELECTIVE ADDITION OF ORGANOMETALLIC REAGENTS TO CARBONYL COMPOUNDS CHIRALITY... 

R. Noyori and M. Kitamura, Enantioselective addition of organometallic reagents to carbonyl compounds Chirality transfer, multiplication and amplification, Angew. Chem., Int. Ed. Engl. 

Structure and Classification of Alcohols 425 10-3 Nomenclature of Alcohols and Phenols 427 10-4 Physical Properties of Alcohols 430 10-5 Commercially Important Alcohols 433 10-6 Acidity of Alcohols and Phenols 435 10-7 Synthesis of Alcohols Introduction and Review 438 Summary Previous Alcohol Syntheses 438 10-8 Organometallic Reagents for Alcohol Synthesis 440 10-9 Addition of Organometallic Reagents to Carbonyl Compounds 443... 

Two recent publications from Stiir have exploited chelation control in the addition of organometallic reagents to carbonyl compounds to produce effective sjrstems for asymmetric induction. In a study of additions to a-alkoxyketones to give protected 1,2-diols (61) it was found that Grignard reagents in... 

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