Practical C-H functionalization of quinones with boronic acids.

ABSTRACT

A direct functionalization of a variety of quinones with several boronic acids has been developed. This scalable reaction proceeds readily at room temperature in an open flask using inexpensive reagents catalytic silver(I) nitrate in the presence of a persulfate co-oxidant. The scope with respect to quinones is broad, with a variety of alkyl- and arylboronic acids undergoing efficient cross-coupling. The mechanism is presumed to proceed through a nucleophilic radical addition to the quinone with in situ reoxidation of the resulting dihydroquinone. This method has been applied to complex substrates, including a steroid derivative and a farnesyl natural product.