Bulletin of the Chemical Society of Japan p. 2976 - 2983 (1982)
Update date:2022-07-30
Topics:
Akiba, Kin-ya
Ohara, Yoshio
Inamoto, Naoki
Alkylation of 2-substituted 3-methyl- or 3-ethylbenzothiazolines with Meerwein reagents gave 2-substituted 3,3-dialkylbenzothiazolinium tetrafluoroborates (3).The configuration of two alkyl groups on the nitrogen was assigned by NMR spectra and NOE measurement.In the Stevens rearrangement of 3 with lithium diisopropylamide ethyl group showed a much larger migratory aptitude (Et:Me>20:1) than methyl group irrespective of the configuration of 3, and cyclic ammonium ylide with planar ?-type carbanion was proposed as an intermediate. 3 suffered nucleophilic attack at the ring sulfur atom by butyllithium to afford a ring-opened ammonium ylide, which collapses to a radical pair to give unusual Stevens rearrangement product, where o-alkylthiophenyl group migrated selectively in preference to alkyl group, because of stabilization by participation of o-alkylthio group.
View MoreTianjin SPHINX SCIENTIFIC LAB.
Contact:+86-022-66211289
Address:Tianda high-tech Park. No.80,the 4th Avenue
Contact:+36(21)2523420
Address:Head office: 1102 Budapest, SZENT LASZLO TER 24/B. 1/1., HUNGARY / CHINA
MS( MAOSHENG )Chemical CO.,LTD
Contact:+86-519-82726678.82726378
Address:TAOXI INDUSTRY ZONE JINTAN
ShiJiaZhuang Dowell Chemical Co.,Ltd.
website:http://www.dowechem.com
Contact:+86-13463963265
Address:Xiyangling village, high tech Zone, Shijiazhuang,Hebei, China
Contact:0571-86821378 ,86820258,56836287,56830923,
Address:Block D ,20F, Tianyuan Building,No.508, Wensan RD, 310013,Hangzhou Zhejiang China
Doi:10.1246/bcsj.81.562
(2008)Doi:10.1039/c6sc02933g
(2017)Doi:10.1007/BF00474467
()Doi:10.1021/jm000980y
(2000)Doi:10.1080/714040977
(2003)Doi:10.1016/S0022-328X(02)01883-1
(2002)