【摘要】 报道溴化(α-呋喃甲酸基)甲基三苯基鉮(1)在无水碳酸钾存在下,以无水二氯甲烷作溶剂,保持0～5℃下与2-全氟炔酸甲酯(2)反应,高产率地得到加合产物4-(α-呋喃甲酰基)-2-三苯基胂基-3-全氟烷基-3-丁烯酸甲酯(3).加合产物3在V(甲醇):V(水)=9:1溶液中分别于室温、回流和封管120℃三种条件下反应,高产率地得到4-全氟烷基-6-(α-呋喃基)-2-吡喃酮(4)和4-(α-呋喃甲酰基)-3-全氟烷基-3-丁烯酸甲酯(5).化合物4和5可以通过柱层析分离;化合物5为一对Z,E异构体,它们不能通过柱层析分离,但其比例可以由~1H NMR估算得到.研究还发现硅胶对该反应具有催化作用,提出并讨论了反应机理.更多还原

【Abstract】 In the presence of K2CO3, reaction of (α - furoyl)methyl - arsoniumbromide(1) with methyl2- perfluoroalkynoates(2) in methylene chloride at 0 - 5℃ afforded the adduct-methyl 4 - (α -furoyl) - 2 - triphenylarsoranylidene - 3 - perfluoroalkyl - 3 - butenoates(3) in high yield. Hydrolysis of 3 in V(CH3OH): V(H2O) = 9:1 methanolic solution at room temperature, 70℃ and 120℃ in a sealed tube respectively, 4 - perfluoroalkyl - 6 - (α - furyl) - 2 - pyranones(4) and methyl 4 - (α - furoyl) -3 - perfluoroalkyl - 3 - butenoates (5) were obtained in excellent yield. Compounds 4 and 5 could be separated by column chromatography. 5 is a mixture of Z - and E- isomers which couldn’t be separated by column chromatography, but the ratio of Z - and E - isomers could be estimated by 1H NMR. The catalytic hydrolysis of compound 3 with silica gel and the mechanisms for the formation of products are also discussed in this paper.更多还原