本文描述了一种高效、便捷的2-三氟甲基苯并咪唑的合成方法。在 Cu 2 O 催化剂存在下,各种邻苯二胺与六氟乙酰丙酮的环化反应顺利进行,生成 2-三氟甲基苯并咪唑,收率令人满意(高达 >99%)。 CF 3源六氟乙酰丙酮不仅充当环化配偶体,而且充当Cu催化剂的配体。各种合成上有用的官能团,例如卤素原子、氰基和甲氧基羰基,在环化反应过程中保持完整。对该反应机理进行了彻底的研究,确定涉及七元环状二亚胺中间体。
An iron-catalyzed practical synthesis of 2-trifluoromethylarylimidazoles through condensation of o-arylenediamines and hexafluoroacetylacetone followed by intramolecular addition and C–C bond cleavage in one-pot has been developed. A series of title compounds were obtained with up to 99% yield. This method is quite practical and suitable for scalable preparation due to simple experimental procedure
Synthesis of 2-trifluoromethyl benzimidazoles, benzoxazoles, and benzothiazoles <i>via</i> condensation of diamines or amino(thio)phenols with CF<sub>3</sub>CN
method is developed for the synthesis of 2-trifluoromethyl benzimidazoles, benzoxazoles, and benzothiazoles in good to excellent yields by the condensation of diamines or amino(thio)phenols with in situ generated CF3CN. Additionally, the synthetic utility of the 2-trifluoromethyl benzimidazole and benzoxazole products is demonstrated via gram scale synthesis. The mechanisticstudy suggests that the reaction
Efficient syntheses of 2-fluoroalkylbenzimidazoles and -benzothiazoles
作者:Olivier René、Alexandra Souverneva、Steven R. Magnuson、Benjamin P. Fauber
DOI:10.1016/j.tetlet.2012.09.069
日期:2013.1
We report an efficient one-step route to 2-fluoroalkylbenzimidazoles and -benzothiazoles via the condensation of fluorinated carboxylic acids and aromatic diamines or aminothiophenols. Additionally, we describe the syntheses of fluoroalkyl-azabenzimidazoles, -purines, and -imidazolopyrazines. This method is high-yielding with broad scope and is operationally simple with potential application to parallel synthesis. (C) 2012 Elsevier Ltd. All rights reserved.