Nucleophilic Addition Reactions and Functionalization of (3-Methoxyestrone)- and (3,17-Dimethoxyestradiol)manganese Tricarbonyl Complexes

Abstract

Nucleophilic addition of MeMgCl and PhMgBr to the A-ring aromatic steroid complex [(η 6 -3,17-dimethoxyestradiol)Mn(CO) 3 ] + gives stable η 5 -cyclohexadienyl complexes and occurs at the C-1 site meta to the -OMe group when the metal is on the “β” side of the steroid; addition to the “α” analogue is less regioselective due to steric interactions and occurs at C-1, C-2, and C-4. A manganese-mediated procedure is reported for the functionalization of estrone at the C-1 position to give 1-methylestrone in 42% yield.