ketone starting materials with a halide leaving group and an alkene were prepared in one step and heated with glycine or glycine esters to promote a tandem imine formation, cyclization, and dipolar cycloaddition cascade. The chemistry was also feasible with acetylhydrazide. In each case a single stereoisomer of the tricyclic amine or pyrazolidine product was formed and the stereochemistry was verified by
一步制得具有卤化物离去基团和烯烃的简单酮原料,并与甘
氨酸或甘
氨酸酯一起加热,以促进串联
亚胺的形成,环化和偶极环加成级联反应。该
化学用乙酰
肼也可行。在每种情况下,形成
三环胺或
吡唑烷产物的单一立体异构体,并通过单晶X射线衍射验证立体
化学。当与甘
氨酸的反应(由于CO 2的损失而发生的反应)不成功时,可以通过交叉复分解促进级联过程,从而得到提供更具反应性的双极性亲核试剂的
乙烯基砜原料。
吡唑烷的还原裂解得到螺环二胺产物。