Erli Youa, Pinhua Lia, Lei Wang*a,b a Department of Chemistry, Huaibei Coal Teachers College, Huaibei, Anhui 235000, P. R. of China b State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai 200032, P. R. of China Fax: +86(561)3090518; e-Mail: leiwang@hbcnc.edu.cn;