Stereoelectronic control in ring opening of bridge-head nitrogen containing fused azolium salts
作者:András Messner、György Hajós、Géza Tímári
DOI:10.1016/s0040-4020(01)86593-5
日期:1992.9
Reaction of tetrazolopyridinium salts 1 with nucleophiles proceeds through the neutral intermediate 2. Ring opening of this leads to hetarylbutadienes (3,4,5) of different geometries. Experimental support has been provided for the theoretical supposition that 2 before opening up can undergo nitrogen inversion and the two invertomers of this intermediate (2A and 2B) react via the two possible senses
四唑吡啶鎓盐1与亲核试剂的反应通过中性中间体2进行。这样的开环导致不同几何形状的杂芳基丁二烯(3,4,5)。为理论上的假设提供了实验依据,即在打开之前2可以进行氮转化,并且该中间体的两个Invertomer(2A和2B)通过两种可能的旋转感觉进行反应,其中一种在立体电子控制下(2A)。通过这种机制,可以解释意想不到的立体选择性,并且可以预测选择性程度。