Carbonyl group with organometallic reagents

Bicyclic ketones react with organometallic reagents to give the products of addition from the less hindered face of the carbonyl group. 

A,A-disubstituted derivatives 1-5. Amination of Group 1, 2, 11 and 12 organometallic compounds and a-metallated carbonyl compounds with these reagents takes place by a direct introduction of the R1R2N+ group to carbanions and enolates and for completion the reactions require only hydrolytic work-up (Scheme 3). 

In terms of synthons, the Grignard addition to the carbonyl group corresponds to the coupling of R R C (OH) and R synthons. The reverse polarity approach can also be achieved with organometallic reagents providing they bear a protected hydroxyl group. The majority of the conventional... 

Carboxylic acid synthesis with the use of nitrile hydrolysis is preferable to Grignard carbonation when the substrate contains other groups that react with organometallic reagents, such as the hydroxy, carbonyl, and nitro functionalities. 

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