Nickel-Catalyzed 3+1+1 Cycloaddition Reactions of Alkenyl Fischer Carbene Complexes with Methylenecyclopropanes

摘要

The Fischer carbene complex is one of the most versatile organometallic reagents for organic synthesis. There is increasing interest in transition metal mediated or catalyzed reactions of Fischer carbene complexes with alkynes, allenes leading to new forms of reactivity. On the other hand, methylenecyclopropanes (MCPs) have been widely utilized as useful building blocks in organic synthesis. In particular, transition metal catalyzed reactions of MCPs have been used for the synthesis of complex organic molecules. Thus, the reactions of Fischer carbene complexes with MCPs mediated or catalyzed by transition metals are expected to have great potential for the syntheses of highly functionalized organic molecules. However, so far, the reactions of these reactive spices under photochemical and thermal conditions have appeared in only two reports. As a transition metal is expected to catalyze reactions with MCPs at different reaction sites, we report herein the transition metal catalyzed [3+1 + 1] cycloaddition reactions of Fischer carbene complexes with MCPs.