Development of α-Borylmethyl-(Z)-crotylboronate Reagent and Enantioselective Syntheses of (E)-δ-Hydroxymethyl-syn-homoallylic Alcohols via Highly Stereoselective Allylboration

We report herein the development of alpha-borylmethyl-(Z)-crotylboronate reagent and the application in highly stereo- and enantioselective syntheses of (E)-delta-hydroxymethyl-syn-homoallylic alcohols. Starting from 1,4-pentadiene, alpha-borylmethyl-(Z)-crotylboronate was synthesized in two steps with high Z-selectivity and enantioselectivity. Subsequent aldehyde allylboration with the developed boron reagent gave highly enantioenriched (E)-delta-hydroxymethyl-syn-homoallylic alcohols upon oxidative workup.

Automated summary

The study describes the development of a new alpha-borylmethyl-(Z)-crotylboronate reagent and its successful application in highly stereo- and enantioselective syntheses of (E)-delta-hydroxymethyl-syn-homoallylic alcohols. Starting from 1,4-pentadiene, the reagent was synthesized in two steps with high Z-selectivity and enantioselectivity, leading to the formation of highly enantioenriched products upon subsequent aldehyde allylboration.