
Journal of the Chemical Society. Perkin transactions I p. 147 - 153 (1984)
Update date:2022-08-04
Topics:
Birkinshaw, Timothy N.
Gillon, David W.
Harkin, Shaun A.
Meakins, G. Denis
Tirel, Malkom D.
A convenient procedure for preparing N-mono- and NN-di-substituted cyanamides from cyanogen bromide has been developed.N,N-Disubstituted thioureas, obtained from the cyanamides, were condensed with α-bromo-α-cyanoketones to give 5-cyano-2-(N,N-disubstituted amino)thiazoles and with α-bromo-ketones to give 2-(N,N-disubstituted amino)thiazoles.Substitution in the latter products afforded 5-trifluoroacetyl- and 5-nitro-2-(N,N-disubstituted amino)thiazoles; nitration is greatly facilitated by the presence of a 4-aryl group.The average values of the barriers of rotation of the barriers to rotation of the 2-NR2 groups (ΔG<*>298) in the 5-substituted thiazoles were established by variable temperature 1H n.m.r. spectrometry to be 57.4 kJ mol -1 (5-NO2), 56.2 (5-COCF3), and 51.5 (5-CN).I.r. examination showed that the 5-trifluoroacetyl compounds adopt one rotational form preferentially; this is probably the carbonyl O,S-syn-conformation.
View MorePINGYUAN SIHUAN PHARMACEUTICAL CO., LTD
Contact:+86-531-55696072
Address:#2766,yinxiu Road, Economic Development Zone, Pingyuan Country, Shandong Province, China.
Dalian Synco Chemical Co., Ltd.
Contact:+86-411-83635150
Address:Rm 1004, 24, Tangshan Street, Dalian
Shanghai Massive Chemical Technology Co., Ltd.
website:http://www.massivechem.com/
Contact:+86 21 34943721
Address:Room 435, 4th floor, Building 9, No. 2568 Gudai Road,Minhang District, Shanghai,
website:http://www.simagchem.com
Contact:+86-592-2680277
Address:21/F Hualong Office Building,No.6 Hubin East Road, Xiamen,China
Nantong Baokai Chemical Co., Ltd (Hangzhou Baokai Bio-Chemicals Co.,Ltd.)
Contact:+86-513-83886111
Address:No. 68 Suzhou road ,Binjiang Fine Chemical Industrial Park , Beixin town, Qidong city ,Jiangsu province
Doi:10.1002/anie.201510973
(2016)Doi:10.1021/ja074300t
(2007)Doi:10.1016/j.tetlet.2020.152790
(2021)Doi:10.1002/ardp.19843170318
(1984)Doi:10.1021/om00085a024
(1984)Doi:10.1021/ja00907a018
(1963)