19968-50-4Relevant academic research and scientific papers
Access to Thiazole via Copper-Catalyzed [3+1+1]-Type Condensation Reaction under Redox-Neutral Conditions
Tang, Xiaodong,Yang, Jidan,Zhu, Zhongzhi,Zheng, Meifang,Wu, Wanqing,Jiang, Huanfeng
, p. 11461 - 11466 (2016/11/28)
A new strategy for thiazoles via copper-catalyzed [3+1+1]-type condensation reaction from oximes, anhydrides and potassiumthiocyanate (KSCN) is developed herein. The transformation has good functional group tolerance and various thiazoles were formed smoothly in good to excellent yields under mild reaction conditions. This process involves copper-catalyzed N-O/C-S bond cleavages, activation of vinyl sp2 C-H bond, and C-S/C-N bond formations which are under redox-neutral conditions as well as operational simplicity.
Selective lithiation of 2-methyloxazoles. Applications to pivotal bond constructions in the phorboxazole nucleus
Evans, David A.,Cee, Victor J.,Smith, Thomas E.,Santiago, Keith J.
, p. 87 - 90 (2008/02/11)
(equation presented) R = Alkyl, Vinyl, Aryl 6:7 >95:5 The lithiation of 2-methyloxazoles with alkyllithium and hindered lithium amide bases generally results in the competitive formation of a mixture of 5-lithio-and 2-(lithiomethyl)oxazole isomers. Herein a synthetically useful lithiation method which allows for the selective formation of 2-(lithiomethyl)oxazole is described. Diethylamine has been found to be a kinetically competent proton source that will mediate the equilibration of the kinetically formed 5-lithiooxazole to its more stable 2-(lithiomethyl)oxazole counterpart. Application of this metalation strategy with lithium diethylamide to two important bond constructions relevant to a projected phorboxazole synthesis is presented.
