A Convergent Approach to Coenzyme Q

Abstract

Syntheses of coenzyme Q 3 - 8 are described, as well as related systems such as plastoquinone-5. Preparation of the higher homologues of the ubiquinones relies on two new conjunctive reagents, or “linchpins”, each of which ultimately corresponds to two or three prenyl units. These allow for attachment of a polyprenyl halide at one end, followed by a Ni(0)-catalyzed cross-coupling at the other terminus with a chloromethylated p -quinone.