We then studied the generality of the protocol for more established olefins as partners (Scheme 2C). The products 2s and 2t of cycloaddition with styrene were obtained for both substrate 1a and 1b in excellent yields (82% and 90% respectively). The cis-diastereomer was isolated as the major product for 2s, which is in contrast to what had been observed in the previous studies by Yoon and Lin. 10, 1,1-Diphenyl ethylene can also be used in the reaction, giving product 2u in 84% yield. N-Vinylpyrrolidinone and N-vinylphthalimide, yielded product 2v and 2w in 83% and 55% yield respectively.