Tetrahedron p. 4039 - 4062 (1991)
Update date:2022-09-26
Topics: Experimental Induced
Esch, Peter M.
Boska, Ilona M.
Hiemstra, Henk
Boer, Richard F. de
Speckamp, W. Nico
Cationic ?-cyclization reactions of N-(3-alkenyl)-N-(methoxycarbonyl)acetoxyglycine esters induced by tin tetrachloride in dichloromethane are described.Reactions started and quenched with water at -78 deg C mainly yield cis-4-hydroxypipecolic esters, whereas reactions quenched after warm-up to room temperature provide trans-4-chloropipecolic esters as major products.A mechanistic scheme is advanced which adequately explains these results.The essentials are a rapid cationic aza-Cope equilibrium of the incipient iminium cation, and participation of the ester moiety through formation of a relatively stable bicyclic dioxycarbenium cation as pivotal intermediate.
View Morewebsite:http://www.shochem.com
Contact:021-50800795
Address:No.1043, Halei Rd, Zhangjiang Hi-Tech Park, Shanghai, Postcode 201203, China
SHANXI XINTIANYUAN PHARMACEUTICAL CO., LTD.
website:http://www.tychemical.com
Contact:0086-358-3521713 3521715
Address:No. 1 Yintong Road, Shanxi Jiaocheng Economic Development Zone, Xiajiaying Town, Jiaocheng County, Lvliang City, Shanxi Province, China
Kaiping Genuine Biochemical Pharmaceutical Co.,Ltd.
Contact:+86-750-2881198
Address:No.1, Xinke Road, Shatang Town, Kaiping, Guangdong Province, P.R.China
He Bei Shun Er Chemical Co., LTD.
Contact:86-0311-86996932/86860168
Address:No 18,North street
chengdu firsterchem Pharmaceutical Co., Ltd.
Contact:028-66825849
Address:chengdu
Doi:10.1071/CH9900765
(1990)Doi:10.1016/j.apcata.2014.04.007
(2014)Doi:10.1246/cl.1990.1611
(1990)Doi:10.1002/cber.19681010404
(1968)Doi:10.1016/j.tet.2003.10.073
(2003)Doi:10.1248/cpb.40.3189
(1992)
