Tetrahedron

Ring expansion by in situ tethering of hydroxy azides to ketones: the boyer reaction

V Gracias, KE Frank, GL Milligan, J Aubé

Index: Gracias, Vijaya; Frank, Kristine E.; Milligan, Gregory L.; Aube, Jeffrey Tetrahedron, 1997 , vol. 53, # 48 p. 16241 - 16252

Full Text: HTML

Citation Number: 57

Abstract

Although alkyl azides can react with ketones to form ring-expanded lactams, the reaction suffers from poor generality and the need to use powerful Lewis acid promotion. The reactions of 1, 2-and 1, 3-hydroxyalkyl azides with ketones yield N-hydroxyalkyl lactams in high yields under the action of protic or Lewis acids such as BF3· OEt2. The reaction appears to succeed due to the initial formation of a hemiketal, which then renders the ...