Intramolecular Reactions of Benzylic Azides with Ketones: Competition between Schmidt and Mannich Pathways
作者:Aaron Wrobleski、Jeffrey Aubé
DOI:10.1021/jo001367p
日期:2001.2.1
The Lewis acid-promoted reactions of benzylic azides with ketones can proceed by two major pathways. The azido-Schmidt reaction involves simple addition of azide to the ketone followed by rearrangement and ring expansion. In addition, benzylic azides can undergo prior rearrangement to afford iminium ions that can subsequently participate in a Mannich reaction. A series of ketones containing an alpha CH2(CH2)nCH(N3)Ph
路易斯酸促进的苄基叠氮化物与酮的反应可以通过两个主要途径进行。叠氮基-施密特反应涉及将叠氮化物简单地添加到酮中,然后重排和扩环。另外,苄基叠氮化物可先进行重排以提供亚胺离子,其随后可参与曼尼希反应。制备了一系列含有αCH2(CH2)nCH(N3)Ph取代基(n = 1-3)的酮,以研究产物对酮环尺寸和系链长度的依赖性。对于所有检查的酮类,当使用四碳连接剂时(上述配方中的n = 1),由于分子内Schmidt反应而获得的双环内酰胺的收率很高,但曼尼希产品主要用于较长的拴系剂(n = 2,3)。 )。