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Synthesis of Antiviral Tetrahydrocarbazole Derivatives by Photochemical and Acid-catalyzed C-H Functionalization via Intermediate Peroxides (CHIPS)
Published on: June 20, 2014
Are the 11-oxo-steroids really so hindered towards organometallic compounds?
Vincent Lecomte1, Elie Stéphan, Jacqueline Vaissermann
1Laboratoire de Chimie organométallique, Ecole Nationale Supérieure de Chimie et CNRS, 11 rue Pierre et Marie Curie, 75005 Paris, France.
Abstract:
Allylation of an 11-oxo-steroid, the protected adrenosterone, was studied to examine more closely the steric hindrance of such a ketosteroid. While the beta face exhibits, as well known, a strong steric hindrance, the alpha side appears to be only relatively hindered. A high diastereoselectivity was observed in the addition of crotyl magnesium bromide.
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