Ligand-controlled gold catalyzed highly site-selective carbene transfer in C-H bond formation
The use of transition-metal catalysts for the transfer of carbene units from diazo compounds constitutes a powerful tool in organic synthesis ”1”.Although several metals such as rhodium,copper,silver and palladium have been reported to mediate this transformation effectively,how to modify the reactivity and selectivity of the carbene while still maintaining its reactivity toward carbon-hydrogen insertion was the challenge task.Recently,Xi,Shi et al.”2” and Yu,Zhang et al.”3” independently have realized the ligand-controlled gold-catalyzed highly siteselective insertion of a carbene into a carbon-hydrogen bond with diazo compounds.A different chemoselectivity of carbene transfer in C-H functionalization using gold catalyst was also observed for the reaction between phenol and methyl phenyldiazoacetate.Whereas the copper catalyst has been shown to efficiently catalyze the O-H insertion reaction ”4” and the dirhodium catalyst exclusively promoted the benzylic C-H insertion ”5” (Fig.1).
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2015-05-08（万方平台首次上网日期，不代表论文的发表时间）
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