作者:Karel Pomeisl、Jaroslav Kvíčala、Oldřich Paleta
DOI:10.1016/j.jfluchem.2006.05.012
日期:2006.10
6a–8a during the process. The reaction of the (E)-butenoates 6a–8a with boron trifluoride led to furanone 14, while in Z-isomers 6b–8b both alkoxy group and vinylic fluorine were substituted with bromine during the reaction. Mechanisms for both complex reactions have been proposed. Furanone 14 was transformed to 2-[tert-butyl(dimethyl)silyloxy]-3-fluoro-4,5-diphenylfuran (18) as a novel building block
乙基(的混合物ë) -和(Ž)-4-烷氧基-2-氟-3,4-二苯基丁-2- enoates(6 - 8)从苯偶姻醚和乙基制备的2-(二乙氧基磷酰基)-2-氟乙分别在室温下使用溴在四氯甲烷中的高收率转化为目标3-氟-4,5-二苯基呋喃-2(5 H)-one(14)。在此过程中,不可环化的Z-异构体6b - 8b逐渐异构化为可环化的E-异构体6a - 8a。(E)-丁烯酸酯6a - 8a的反应用三氟化硼生成呋喃酮14,而在Z-异构体6b - 8b中,烷氧基和乙烯基氟在反应过程中均被溴取代。已经提出了两种复杂反应的机理。将呋喃酮14转化为2- [叔丁基(二甲基)甲硅烷氧基] -3-氟-4,5-二苯基呋喃(18)。