摘要
The asymmetric alkylation reactions induced by non-cross-linked polystyrene supported cyclosulfamide chiral auxiliary occurred in moderate to good yields with a very high stereoselectivity（e.e.〉99%）. Compared to non-supported cyclosulfamide chiral auxiliary, this chiral auxiliary can be recovered by simple precipitation and filtration, and could be reused at least four cycles without appreciable reduction in the yield or stereoselectivity.
The asymmetric alkylation reactions induced by non-cross-linked polystyrene supported cyclosulfamide chiral auxiliary occurred in moderate to good yields with a very high stereoselectivity（e.e.〉99%）. Compared to non-supported cyclosulfamide chiral auxiliary, this chiral auxiliary can be recovered by simple precipitation and filtration, and could be reused at least four cycles without appreciable reduction in the yield or stereoselectivity.
基金
Supported by the National Natural Science Foundation of China（No.21342002） and the College Students＇ Innovation and Entrepreneurship Training Plan of Hubei Province of China（No.201310512013）.
