Potassium tert-Butoxide-Mediated Isomerization of Alkenes: A Versatile Protocol for Miscellaneous Substrates

TL;DR

A new and efficient method for isomerizing alkenes using potassium tert-butoxide is presented, working under mild conditions and yielding stable products.

Contribution

A general and efficient protocol for alkene isomerization using KOtBu as base and proton shuttle under mild conditions.

Findings

The method works for various substrates including benzenes, heterocycles, and sulfones.

KOtBu acts as both base and proton shuttle, enabling reactions under air with high yields.

The reaction produces the most stable isomer (typically E-alkene) under thermodynamic control.

Abstract

The development of
rapid and efficient routes to alkene derivatives
remains a significant priority due to their broad utility as building
blocks and valuable compounds. Herein, we report a simple, general,
and highly efficient procedure for the (catalytic) isomerization of
alkenes under mild conditions. This method is applicable to a wide
range of substrates, including allylic derivatives of benzenes, aromatic
and aliphatic systems, heterocycles, ethers, thioethers, amines, and
sulfones. In this transformation, KO
t
Bu
acts as both the base and the proton shuttle, enabling the reaction
to proceed under air and affording quantitative yields within minutes
for the majority of the substrates examined. The reaction occurs under
thermodynamic control, affording the most stable isomer (typically,
the E-alkene).

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