The reactions of carbonyls with a low-valent titanium reagent prepared by TiCl4with Mg in THF were carried out under ultrasonic action at room temperature for 10 min to1 h and corresponding olefins were obtained in go...The reactions of carbonyls with a low-valent titanium reagent prepared by TiCl4with Mg in THF were carried out under ultrasonic action at room temperature for 10 min to1 h and corresponding olefins were obtained in good yields. The results indicate that the titanium-induced reductive coupling of carbonyls to olefins is directly affected by ultra sonic dueto the electron transfer process.展开更多
文摘The reactions of carbonyls with a low-valent titanium reagent prepared by TiCl4with Mg in THF were carried out under ultrasonic action at room temperature for 10 min to1 h and corresponding olefins were obtained in good yields. The results indicate that the titanium-induced reductive coupling of carbonyls to olefins is directly affected by ultra sonic dueto the electron transfer process.
文摘通过对 6 2个羰基化合物中羰基 13 C NMR谱化学位移与其部分结构参数关系研究 ,发现羰基13 C NMR谱化学位移与烷基极化效应指数 (PEI)、部分电荷 (qx)的关系可用下式表示 :δ =a +b∑PEI+c∑qx该式能比现有文献方法较好地表达羰基13 C NMR谱化学位移值随结构变化的规律 ,从而对解析13 CNMR谱及预测羰基13 C
