Reaction of α,β-unsaturated and α-phenyl acetals with epoxides, promoted by lithium. Potassium mixed base LICKOR: Synthesis of homoallyl alcohols
作者:Annamaria Deagostino、Cristina Prandi、Paolo Venturello
DOI:10.1016/0040-4020(95)00969-8
日期:1996.1
Acetals 1, 7 and 8, in the presence of the mixed metal base LICKOR, undergo deprotonation and elimination reactions, affording enol ethers intermediates. Further hydrogen-metal exchange at the α-vinyl site of elimination products gives α-metalated species that yield, by reaction with epoxides, homoallyl alcohols. Experimental procedures are given for the conversion of the unsaturated species into the
缩醛1,7和8,在混合金属基底LICKOR的存在下,进行脱质子化和消除反应,得到烯醇醚中间体。在消除产物的α-乙烯基位点进一步进行氢-金属交换,得到α-金属化的物种,该物种通过与环氧化物反应生成均烯丙基醇。给出了将不饱和物质转化为相应的羰基化合物的实验程序。α-取代的乙氧基二烯4也是一锅合成2,6-二取代的四氢-4 H-吡喃-4-酮19的有用中间体。