Iodine‐Promoted Metal‐Free Aromatization: Synthesis of Biaryls, Oligo <i>p</i>‐Phenylenes and A‐Ring Modified Steroids

Abstract

Abstract We describe efficient procedures based on the use of iodine for the synthesis of biaryls from arylcyclohexenols or arylcyclohexanols using sub‐stoichiometric/catalytic iodine and dimethyl sulfoxide (DMSO) as oxidant. Heteroarylcyclohexanols also produced the corresponding biaryl products. It was proven that biphenyl can also be efficiently obtained when the quantity of iodine was reduced to 0.05 equiv. The method is compatible with different functional groups in the aromatic ring (either electron‐donating or electron‐withdrawing groups). For substrate scope, apart from cyclohexanone and cyclohexenone, some substituted cyclohexanones were also used to synthesize the starting arylcyclohexanols. The process was applied to the synthesis of oligo p ‐phenylenes and A‐ring aromatized steroids, where the combined use of I 2 /DMSO not only provoked the necessary migration of the methyl group at C‐10, but also further extended the conjugation. magnified image