One-pot, high yield synthesis of alpha-ketols from Delta5-steroids
Jorge A R Salvador1, Vânia M Moreira, James R Hanson
1Laboratório de Química Farmacêutica, Faculdade de Farmácia, Universidade de Coimbra, Rua do Norte, 3000-295 Coimbra, Portugal. salvador@ci.uc.pt
Abstract:
Alpha-hydroxy ketones (alpha-ketols) are present in many compounds with biological activity. Several methods are available for the preparation of alpha-ketols but only a few of them describe the synthesis of steroid alpha-ketols from olefins. In this work, a new system consisting of KMnO(4)/Fe(ClO(4))(3).nH(2)O was used in order to achieve the direct conversion of Delta(5)-steroids to their corresponding alpha-ketols, in high yields. Consideration of the probable reaction mechanism is provided. 2D homo- and heteronuclear correlation NMR spectroscopic techniques were used to assign (1)H and (13)C resonances of some synthesized compounds. This method has potential for the preparation of alpha-hydroxy ketones of biological interest.
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