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 MoreChiral Quest (Suzhou) Company Ltd
website:http://www.chiralquest.com
Contact:+86-0512-62956066
Address:B1/9, 218 Xinghu Street, Suzhou Industrial Park
Linyi Shengxin Pharmaceutical R&D Co., Ltd
Contact:+86-18653953873
Address:West First of Yufeng Road, Yishui County
Contact:0086 371 65711996
Address:Jalan 4/3, Kawasan Perindustrian Serendah, 48000 Rawang,
Shanghai Hanshare Industry Co.,Ltd.
Contact:86 21 20960688
Address:RM902-903,Building E, Wanda Plaza,No.26,Zhoukang Road, Pudong District, Shanghai, China
Shandong Dayi Chemical Co., Ltd.
website:http://www.dayi.com.cn
Contact:+86- 535-7388728. 15306386031
Address:No 1 Danya west road, Laiyang City, Shandong province
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)
