Question

H CH3 1. LDA 2. CHal НН H3C CN H3C CN Monocarbonyl compounds can be alkylated at the a position via the use of lithium disopropylamide, a strong, sterically hindered base Because only one carbonyl group is available to participate in resonance stabilization of the enolate, the a-hydrogens are less acidic than those of P-dicarbonyl compounds and so a stronger base is necessary to completely convert the compound to the enolate. The reaction occurs in a pola aprotic solvent such as THF. Compounds such as esters, ketones, and nitriles are commonly alkylated via this procedure Aldehydes, howerw rarely give high yields in this procedure because they tend to undergo carbonyl condensation instead Draw curved arrows to show the movement of electrons in dhis step of the mechanism Arrow pushing Instructions H CH3 H3C CN . N:

Answer 1