更正

第106页表1的表注a更正为:Reaction conditions:A mixture of la(0.20 mmol),2a(0.50 mmol),oxidant(0.24 mmol),catalyst(5 mol%)and base(0.4 mmol)in the solvent(2.0 mL)was stirred at r.t.;For Entries 6?20.2a(0.6 mmol)and catalyst(10 mol%)were used;For Entry 11,no loss of chemical yield was detected when catalyst loading was reduced to 5 mol%.另外,原题目及文中“氮杂卡宾”更严谨的表述为“氮杂环卡宾”.