Reduction of Tertiary Amides with Borane in the Presence of Trimethyl Borate

摘要

Various tertiary amides have been subjected to the reduction by borane-THF in the presence of trimethyl borate at 0∩ and the product ratio of alcohol and amine have been analyzed in order to find out the possible way to obtain one product exclusively on the basis of the structure of amides. In the case of N,N-dimethyl derivatives of both linear aliphatic and aromatic amides the corresponding alcohols were produced predominantly. However, the bulkier tertiary amides such as N,N-diethyl and hindered acid derivatives afforded amines rather than alcohols. The mechanism of borane reduction of tertiary amides is also discussed.