Synthesis and characterisation of N,N-disubstituted 2-amino-5-acylthiophenes and 2-amino-5-acylthiazoles
摘要:
Starting from halomethyl-ketones 8 and N,N'-persubstituted thioacrylamides 7 or their 2-aza analogues 11 a series of N,N-disubstituted 2-amino-5-acylthiophenes 10 and 2-amino-5-acylthiazoles 12, respectively are available. By starting from 1,3-dichloroacetone and using the same thioacrylamide derivatives 7 and 11 N,N-disubstituted 2-amino-5-(chloroacetyl)thiophenes 13 and 2-amino-5-(chloroacetyl)thiazoles 14 as well as N,N'-persubstituted bis-(2-amino-5-thienyl)ketones 15, 2-amino-5-thienyl-(2-amino-5-thiazolyl)ketones 16, and bis-(2-amino-5-thiazolyl)ketones 17, respectively are available. (C) 2002 Elsevier Science Ltd. All rights reserved.
Orthoamide. IL. Umsetzungen von Orthoamid-Derivaten mit Schwefel und Selen, Synthesen von 1,3-Thiazol- und 1,3-Selenazolderivaten
作者:W. Kantlehner、Michael Hauber、Markus Vettel
DOI:10.1002/prac.19963380180
日期:——
N,N-Dimethylformamide acetal reacts with elemental selenium to give a mixture of selenocarbonic acid derivatives 2 and 3, which can be converted to the pure N,N-dimethylcarbamidic acid Se-methylester 2 by treatment with methyl iodide. Analogously from the orthoformic acid derivatives 5 and 6 and selenium the N,N,N',N'-tetramethyl-selenurea 7 can be prepared. In the reaction of 12 with elemental sulfur and selenium the amidines 14 and 15, respectively, are formed. By treatment of 14 and 15 with alpha-halogenated carbonyl compounds and triethylamine the 1,3-thiazoles 18 and 1,3-selenazoles 19 can be prepared. The synthesis of the propynoic acid orthoamide 26b is described. 26b reacts with the guanidinium salt 24b to give the bis-orthoamide of butynedioic acid 20b. Other orthoamides of butynedioic acid 20b-20e can be synthesized from the orthoamide 20a by transamination. The thiolation of the orthoamides affords the bis-amidinium-dithiolates 21a-c, which can be alkylated to give the bis-amidinium salts 27. By treatment with alpha-halogene carbonyl compounds and triethylamine the dithiolates 21a-e are cyclized to give thieno [3,2b] thiophenes 28a-n. The quadrupoles 21 undergo cycloadditions with dimethyl-butynedioate which afford the bis(3H-thiophene-2 ylidenes) 29a-c. Treatment of 29a with methyl tosylate gives rise to the dithiophene 30a. The dithiophene 30b can be obtained by heating 21b with dimethylbutynedionate.
Facile Synthesis of 5-Acyl-2-amino- 1,3-thiazole by the Reaction of Thiaazadienes with a-Halo Ketones
作者:Edward R. Biehl、Ramadas Sathunuru
DOI:10.3987/com-04-10231
日期:——
Chehna, M.; Pradere, J. P.; Guingant, A., Synthetic Communications, 1987, vol. 17, # 16, p. 1971 - 1976
作者:Chehna, M.、Pradere, J. P.、Guingant, A.
DOI:——
日期:——
Facile Synthesis of 2-Substituted 4H-1,3-Thiazines and 3-Substituted 1,2-Isothiazoles via Benzyne Intermediates
作者:Edward R. Biehl、Ramadas Sathunuru、Hongming Zhang、Charles W. Rees、Edward Biehl
DOI:10.3987/com-05-10414
日期:——
CHEHNA, M.;PRADERE, J. P.;GUINGANT, A., SYNTH. COMMUN., 17,(1987) N 16, 1971-1976