Catalytic Substrate-Selective Silylation of Primary Alcohols via Remote Functional-Group Discrimination.

Silylation of alcohols has generally been known to take place at the sterically most accessible less-hindered hydroxy group. Herein, the catalyst-controlled substrate-selective silylation of primary alcohols, in which the selectivity was controlled independently of the innate reactivity of the hydroxy group, based on the steric environment, is reported. The chain-length-selective silylation of 1,n-amino alcohol derivatives was achieved and 1,5-amino alcohol derivatives showed outstandingly high reactivity in the presence of analogues with a shorter or longer chain length under catalyst-controlled conditions. A highly substrate-selective catalytic silylation of pentanol analogues was also developed, in which the remote functionality at C(5) from the reacting hydroxy groups was effectively discriminated on silylation.