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 MoreContact:+44 7958 511245
Address:PO Box 469, Manchester, UK
Changsha Nutritopper Bio Technology Co.,Ltd.
Contact:+86-731-87803543
Address:East 1st Street, Baima Road, Ningxiang County
Shanghai birch chemical technology co.,ltd
Contact:+86-21-54096810
Address:No.2588,Jungong Road,Shanghai,China
Zouping Fuhai Technology Development Co., Ltd.
Contact:+0532-86934525 18660293207
Address:jiuhu town industrial park Zouping County,bingzhou Provincejiuhu town industrial park
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)
