Kinetic Resolution of Allylic Alcohol with Chiral BINOL-Based Alkoxides: A Combination of Experimental and Theoretical Studies.

Abstract

The development and characterization of enantioselective catalytic kinetic resolution of allylic alcohols through asymmetric isomerization with chiral BINOL derivatives-based alkoxides as bifunctional Brønsted base catalysts were described in the study. A number of chiral BINOL derivatives-based alkoxides were synthesized, and their structure-enantioselectivity correlation study in asymmetric isomerization identified a promising chiral Brønsted base catalyst, which afforded various chiral secondary allylic alcohols (ee up to 99%, S factor up to >200). In the mechanistic study, alkoxide species were identified as active species and the phenol group of BINOL largely affected the high reactivity and enantioselectivity via hydrogen bonding between the chiral Brønsted base catalyst and substrates. The strategy is the first successful synthesis strategy of various chiral secondary allylic alcohols through enantioselective transition-metal-free base-catalyzed isomerization. The applicability of the strategy had been demonstrated by the synthesis of the bioactive natural product (+)-veraguensin.