Über eine neue Methode zur positionsselektiven Einführung von Trifluormethyl-Gruppen in Heteroaromaten, Teil 2.1Nucleophile Substitution an 5-fluor-4-trifluormethyl-substituierten 1,3-Azolen
Über eine neue Methode zur positionsselektiven Einführung von Trifluormethyl-Gruppen in Heteroaromaten, Teil<sup>1</sup>. Synthese von trifluormethyl-substituierten 1,3-Azolen (Oxazole, Thiazole, Imidazole)
作者:Klaus Burger、Klaus Geith、Dieter Hübl
DOI:10.1055/s-1988-27509
日期:——
A New Method for Regioselective Introduction of Trifluoromethyl Groups into Heteroarenes; Part 1. Synthesis of Trifluoromethyl-substituted 1,3-Azoles (Oxazoles, Thiazoles, Imidazoles) The reaction of 4,4-bis(trifluoromethyl) -substituted hetero-1,3-dienes [N-(Hexafluoro-2-propylidene)carboxamides, -thiocarboxamides, and -amidines] with tin(II) chloride affords 5-fluoro-4-trifluoromethyl- oxazoles, -thiazoles, and -imidazoles, respectively. The reaction sequence involves heterocyclic tin(IV) compounds as intermediates.
Selektive einführung von fluor und trifluormethylgruppen in heterocyclische systeme [1] synthese von 5-fluor-4-trifluormethyl-oxazolen
作者:Klaus Burger、Herbert Goth
DOI:10.1016/s0022-1139(00)82267-8
日期:1981.6
N[1-Chlorodifluoromethyl-2,2-difluoro(vinyl)]-imidoylchlorides 4 on heating with trimethyl phosphate yield 5,5-difluoro- 4-difluoromethylen-2-oxazolines 5. In the presence of caesium fluoride the latter rearrange to give 5-fluoro-4-trifluoromethyl- oxazoles 6. Compounds 6 on treatment with nucleophiles give 4-trifluoromethyl-oxazoles 7.
N [1-氯二氟甲基-2,2-二氟(乙烯基)]-亚氨基酰氯4在与磷酸三甲酯一起加热的情况下产生5,5-二氟-4-4-二氟亚甲基-2-恶唑啉5。在氟化铯存在下,后者重排以得到5-氟-4-三氟甲基-恶唑6.用亲核试剂处理的化合物6得到4-三氟甲基-恶唑7。