Catalytic Silane‐Reduction of Carboxylic Esters and Lactones: Selective Synthetic Methods to Aldehydes, Lactols, and Ethers via Silyl Acetal Intermediates

Abstract Practical procedures for the production of aldehydes, lactols, and ethers are offered by the palladium‐catalyzed silane‐reduction of carboxylic esters and lactones. The partial reduction of carboxylic esters or lactones with 1,1,3,3‐tetramethyldisiloxane in the presence of commercially available palladium on carbon (Pd/C) and some copper compounds as a co‐catalyst smoothly proceeds under mild conditions to afford the silyl acetal derivatives in high yields, which are easily converted to the corresponding aldehydes or lactols by hydrolysis of silyloxy group. On the other hand, deoxygenated ethers are obtained with high selectivity by treatment of silyl acetals with catalytic amounts of Me 3 SiOTf at –78 °C or stoichiometric amounts of BF 3 •OEt 2 at ambient temperature.