Stereoselective epoxide generation with cyclic rhodium carbenoids: A new access to spiro-indolooxiranes

The reaction of cyclic diazoamides with aryl aldehydes catalyzed by rhodium(II) acetate leads to intermolecular stereoselective epoxide ring formation. A series of spiro-indolooxiranes has been synthesized following the described method in a facile manner. The use of aryl dialdehydes in the course of reaction of cyclic diazoamide resulted the formation of bis-spiro-indolooxiranes