Ring Opening of Methylenecyclopropane Moieties in the Palladium-Catalyzed Cross-Coupling of Methylenecyclopropyl Bromides with Metallated CH-Acidic Compounds
作者:Melanie Brandl、Sergei I. Kozhushkov、Stefan Bräse、Armin de Meijere
DOI:10.1002/(sici)1099-0690(199803)1998:3<453::aid-ejoc453>3.0.co;2-2
日期:1998.3
Palladium-catalyzed cross-coupling reactions of bromo(methylenecyclopropanes) 1c, 2c with the sodium enolate of dimethyl malonate 4a and the chlorozinc enolates of the glycine equivalent (diphenylmethyleneamino)acetate 4c and diethyl malonate 4d, respectively, have been found to proceed with opening of the three-membered ring in each case, to give the corresponding dienyl-substituted CH-acidic compounds
已发现溴(亚甲基环丙烷)1c、2c 与丙二酸二甲酯 4a 的烯醇钠和甘氨酸等价物(二苯基亚甲基氨基)乙酸酯 4c 和丙二酸二乙酯 4d 的氯锌烯醇化物的钯催化交叉偶联反应分别进行三元环在每种情况下,以中等至良好的产率得到相应的二烯基取代的 CH-酸性化合物 5-7。另一方面,双环亚丙基氯化锌 (2d) 与溴丙二酸二乙酯 (4e) 和亲电甘氨酸等价物 2-乙酰氧基-2-(二苯基亚甲基氨基)乙酸乙酯 (4f) 的偶联分别得到 7 和 6,产率分别为 27% 和 29%。