Journal of the Chemical Society. Perkin transactions I p. 1953 - 1962 (1981)
Update date:2022-08-03
Topics:
Mageswaran, Sivapathasuntharam
Ollis, W. David
Sutherland, Ian O.
The allylic ammonium ylides (22) and (47) and sulphonium ylide (53) are isolable, usually as crystalline solids, because their <3,2> sigmatropic rearrangements are inhibited by the strain associated with the bicyclic transition state of a concerted reaction mechanism.The tetrahydropyridinium (22) and dihydrothiopyranium (29) ylides undergo a thermal <3,2> rearrangement, but the pyrrolinium ylide (47) rearranges by a <1,2>, rather than a <3,2>, sigmatropic pathway.The dihydrothiophenium ylide (53) does not undergo either a <1,2> or <3,2> sigmatropic rearrangement but instead reacts in a bimolecular fashion to give eventually buta-1,3-diene, 2,5-dihydrothiophen, and the heterocycle (55).The <3,2> rearrangements of the ylides (22) and (29) follow predominantly an endo-pathway leading to a single diastereomer of the products (23) and (31); this strong endo preference is not shown by analogous acyclic ammonium ylides.
View MoreShanggao Ruiya Fine Chemicals Co., Ltd
Contact:+86-795-2592103
Address:Xingguang Nanlu,Shanggao County Industry Park
Shanghai Yuking Water Soluble Material Tech Co., Ltd
Contact:86-21-68286299
Address:4F, 13B, No. 600, South Xinyuan Road 201306, Shanghai, China
Jiangsu Zenji Pharmaceuticals LTD
Contact:+86-025-83172562; +1-224-888-1133(USA)
Address:No.5 Xinmofan Road
Contact:13120882795；+86-21-34621078;+86-021-31122318
Address:Suite 2,No.2715 Longwu Road
website:http://www.china-sinoway.com
Contact:+86-592-5853819
Address:16/F,Huicheng Comm,Complex,No839 XiaHe Rd, Xiamen,China
Doi:10.3987/com-04-10169
(2004)Doi:10.1002/ejoc.200300774
(2004)Doi:10.1021/jo050112e
(2005)Doi:10.1021/ol050372i
(2005)Doi:10.1007/s11137-005-0002-0
(2004)Doi:10.1016/j.bmcl.2005.03.005
(2005)
