Diastereoselectivity Control of the Radical Carboazidation of Substituted Methylenecyclohexanes
作者:Sylvaine Cren、Pascal Schär、Philippe Renaud、Kurt Schenk
DOI:10.1021/jo900088x
日期:2009.4.17
A systematic study of the diastereoselectivity of the radical carboazidation of methylenecyclohexane derivatives is presented. Several substitution patterns leading to a high level of stereocontrol have been identified. Axial attack is the preferred reaction pathway for cyclohexyl radicals, and excellent stereoselectivities can be obtained by introducing an axial substitutent at position 2. In this
对亚甲基环己烷衍生物的自由基碳叠氮化的非对映选择性进行了系统的研究。已经确定了导致高水平立体控制的几种取代模式。轴向攻击是环己基自由基的优选反应途径,通过在位置2引入轴向取代基可以获得优异的立体选择性。在这种情况下,可以耐受位置2的第二赤道取代基,而对非对映选择性没有很大的不利影响。最后,观察到高水平的赤道攻击,在位置2有非常大的取代基。