2-propanol. The copper catalysts are not only inexpensive compared to rhodium complexes, but they also exhibit better functional group compatibility with aromatic aldehydes and ketones. Indeed very high yields were obtained for the formation of styrenes containing nitro, trifluoromethyl, amino, and ester groups, as well as for pyridine-, pyrrole-, and indole-substituted alkenes.
(NHC)-Cu(NHC = N-杂环卡宾)配合物在三甲基甲
硅烷基
重氮甲烷,
三苯基膦和2-
丙醇的存在下有效催化了各种脂肪族和
芳香族醛和酮的甲基化反应。与
铑配合物相比,
铜催化剂不仅价格便宜,而且与芳族醛和酮的官能团相容性也更好。实际上,对于形成含有硝基,三
氟甲基,
氨基和酯基的
苯乙烯,以及
吡啶,
吡咯和
吲哚取代的烯烃,都获得了很高的产率。