Exploring New Reactivity of Metal Carbenoids and its Application to Organic Synthesis

Metal carbenoids exhibit unique reactivities towards stable chemical bonds. Such reactive species are recognized as powerful tools for direct functionalization of unactivated compounds. Meanwhile, the high and versatile reactivity of metal carbenoids sometimes become problematic in the development of chemoselective reactions, because organic molecules often include some reactive sites to metal carbenoids such as C-H bonds, multiple bonds, and heteroatoms. Therefore, considerable efforts have focused on the control of chemoselectivity of metal carbenoid-mediated reactions in recent years. We have been interested in the potential of metal carbenoids to develop an unusual reaction and succeeded in developing catalyst-controlled highly chemoselective reactions for the synthesis of complex molecules. Herein we summarized our achievements; an insertion reaction of Rh-carbenoid into an amide C-N bond and a dearomative ipso-Friedel-Crafts (DIFC) reaction mediated by chiral Ag-carbenoid species. An application of the amide insertion reaction to the natural product synthesis is also described.