Donor Rhodium Carbenes by Retro‐Buchner Reaction

Successful iteration: Donor rhodium(II) carbenes are generated by retro‐Buchner reaction (decarbenation) of 7‐substituted 1,3,5‐cycloheptatrienes, leading to broad‐scope synthesis of allylsilanes by Si−H insertion and a new method for the iterative vinylogation of aldehydes.

Abstract

Rhodium carbenes are key intermediates in a range of cycloadditions and insertion reactions. Herein, we report the first generation of donor Rh^II carbenes by decarbenation of 7‐substituted 1,3,5‐cycloheptatrienes. This discovery unlocks an improved retro‐Buchner‐cyclopropanation sequence, a Si−H insertion reaction for a broad‐scope synthesis of allylsilanes, and a new method for the vinylogation of aldehydes. The last strategy led to the development of an iterative synthesis of E‐polyenes, and to the total synthesis of navenones B and C.

from A via a.sfakia on Inoreader http://bit.ly/2FJbiVN