Metal coordination-directed hydroxylation of steroids with a novel artificial P-450 catalyst
Zhenglai Fang1, Ronald Breslow
1Department of Chemistry, Columbia University, New York, New York 10027, USA.
Abstract:
[structure: see text] A novel catalyst has been synthesized in which a manganese-porphyrin unit is linked to two 2,2'-bipyridyl groups and two pentafluorophenyl groups in trans fashion on its four meso positions. Relative to a previous catalyst in which the manganese-porphyrin had four 2,2'-bipyridyl groups, the new catalyst, in the presence of Cu(2+) ions as coordinating linkers, catalyzes the oxidation of a steroid substrate with much better regioselectivity and higher turnover numbers.
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