Reduction of α-trialkylsiloxy nitriles with diisobutylaluminium hydride (DIBAH): A facile preparation of α-trialkylsiloxy aldehydes and their derivatives
could be achieved via the reduction of α-trimethylsiloxy nitriles with diisobutylaluminium hydride (DIBAH) starting from a variety of ketones. The facile synthesis of optically active α-tert-butyldimethylsiloxy aldehydes was attained by combination of asymmetric silylcyanation of aldehydes and DIBAH reduction of optically active α-siloxy nitriles. Furthermore, in the reduction of some α-tert-butyldimethylsiloxy-β
The nature of the O-protecting group is crucial to obtain, in terms of diastereoselectivity and chemical yields, the best results. An abinitiomolecularorbitalstudy on 2-silyloxy propanal and MM2 studies on 2-alkoxy propanal show the existence of stable cyclic and acyclic conformers, which are presumably responsible for the high syn diastereoselectivity observed in the addition of non-metal carrying
LiCl acts as a highlyeffectivecatalyst for cyanosilylation of various aldehydes and ketones to the corresponding silylated cyanohydrins. The reaction proceeds smoothly with a substrate/catalyst molar ratio of 100−100 000 at 20−25 °C under solvent-free conditions. α,β-Unsaturated aldehydes are completely converted to the 1,2-adducts. The cyanation products can be isolated by direct distillation of