Diastereoselective Henry reactions of N,N-dibenzyl α-amino aldehydes with nitromethane catalyzed by enantiopure guanidines

Several enantiopure guanidines are studied as the catalysts of Henry reactions of N,N-dibenzyl α-amino aldehydes with nitromethane. Good diastereoselectivity is observed in the reactions of l-valine or l-isoleucine derived aldehydes catalyzed by a (R)-1-(1-naphthyl)ethylamine derived guanidine.