Spectroscopic studies on the TiCl4-promoted reaction of allylsilanes with aldehydes and α,β-enones
作者:Scott E. Denmark、Neil G. Almstead
DOI:10.1016/0040-4020(92)80007-3
日期:1992.7
established by metathesis of the corresponding silyl ether. No metathesis of the allylsilane occurred before addition. The reaction of allyltrimethylsilane with TiCl4-complexed enones was also studied. A titanium enolate was observed spectroscopically as the intermediate in this reaction. No metathesis of the allylsilane occurred before addition to the complexed enone.
用光谱法研究了正庚醛和4-(正庚基)苯甲醛与TiCl 4的络合。观察到形成的络合物的性质取决于所存在的TiCl 4的化学计量。亚化学当量的TiCl 4优选2:1(路易斯碱/ TiCl 4)配合物,而当存在过量的TiCl 4时则优先形成1:1配合物。预络合的醛与烯丙基三甲基硅烷的反应导致形成钛醇盐,其结构通过相应甲硅烷基醚的复分解独立地建立。在添加之前没有发生烯丙基硅烷的复分解。烯丙基三甲基硅烷与TiCl 4的反应还研究了复杂的烯酮。在光谱上观察到烯醇钛作为该反应的中间体。加入络合的烯酮之前,没有发生烯丙基硅烷的复分解反应。