Stereoselective electrogeneration of (E)-4-alkoxy-2-phenyl-5-chloro-2-oxazolines by cathodic reduction of N-(1-alkoxy-2,2,2-trichloroethyl)benzamides
作者:Antonio Guirado、Raquel Andreu、Bruno Martiz、Jesús Gálvez
DOI:10.1016/j.tet.2003.11.033
日期:2004.1
compounds has been established. Quantitative reactions of benzamides with chloral hydrate provided chloralbenzamides which were efficiently converted to N-(1,2,2,2-tetrachloroethyl)amides by treatment with phosphorus pentachloride. These compounds reacted selectively with alcohols under mild conditions to give N-(1-alkoxy-2,2,2-trichloroethyl)benzamides in high yields which were stereoselectively transformed
已经建立了合成标题化合物的第一种方法。苯甲酰胺与水合氯醛的定量反应提供了氯苯甲酰胺,通过用五氯化磷处理将其有效转化为N-(1,2,2,2-四氯乙基)酰胺。这些化合物在温和条件下与醇选择性反应,以高收率得到N-(1-烷氧基-2,2,2-三氯乙基)苯甲酰胺,将其立体选择性地转化为(E)-4-烷氧基-2-芳基-5-氯在非质子介质中,在恒定的阴极电位下,通过电化学还原,-2-恶唑啉的收率基本令人满意。