Bismuth(III) salts mediated regioselective ring opening of epoxides: an easy route to halohydrins and beta-hydroxy nitrates

作者：Pinto Rui M A; Salvador Jorge A R^*; Le Roux Christophe

来源：Tetrahedron, 2007, 63(37): 9221-9228.

DOI：10.1016/j.tet.2007.06.054

• bismuth(III) salts
• epoxysteroids
• halohydrins
• beta-hydroxy nitrates

The ring opening of various epoxides was achieved under mild conditions using bismuth(III) salts. Halohydrins and beta-hydroxy nitrates were efficiently obtained from the corresponding 5 alpha,6 alpha-, 2 alpha,3 alpha-, and 5 beta,6 beta-epoxysteroid using BiCl(3), BiBr(3) or Bi(NO(3))(3) center dot 5H2O. Considerations about the probable reaction mechanism are provided. 2D homo- and heteronuclear correlation NMR spectroscopic techniques were used to unequivocally demonstrate the trans-diaxial nature of the epoxide ring opening.

• 出版日期2007-9-10