Central zinc metal-controlled regioselective meso-bromination of zincated β-silylporphyrins—rapid access to meso,β-dual-functionalized porphyrins

A convenient method for the preparation of meso,β-dual-functionalized porphyrin was developed. The bromination of zincated β-silylporphyrin with NBS selectively yielded meso-bromo-β-silylporphyrin, whereas, the bromination of free-base β-silylporphyrin selectively yielded β-bromoporphyrin via an ipso-substitution of the silyl group. These meso,β-dual-functionalized porphyrins could be used as multipurpose synthons for fabricating various porphyrin derivatives.