Tandem Remote Csp3−H Activation/Csp3−Csp3 Cleavage in Unstrained Aliphatic Chains Assisted by Palladium(II)

Abstract

We report here a proof of concept for the cleavage of unstrained remote Csp3–Csp3 bonds at room temperature assisted by a directing group, opening up new possibilities to use aliphatic carboxylic acids as suitable alkenyl coupling partners. This strategy involves the Pd-mediated Csp3–H activation directed by a tethered 8-aminoquinoline group, followed by a concerted asynchronous carbene insertion into the Pd–C bond, and an unexpected β-carbon-carbon bond splitting. The insertion of a coupling partner into a Pd–C bond is a novel route to promote C–C bond cleavage, which, in contrast to most common methodologies, does not rely on the use of strained carbocycles.