Novel phenanthro[9,10-d]pyrimidines and phenanthro[9,10-d][1,2]oxazoles are regioselectively prepared by the application of a straightforward synthetic pathway, starting from new o,o′-dihalogenated and non-halogenated 4,5-diarylpyrimidines and 4,5-diarylisoxazoles, respectively, prepared via a tandem amine exchange/heterocyclization of diarylenaminones. A comparative study of biaryl coupling methodologies
新型菲[9,10- d ]嘧啶和菲[9,10- d ] [1,2]恶唑是通过从新的o,o开始的直接合成途径进行区域选择性制备的经由串联芳胺交换/二芳基氨基酮制备的′-二卤代和非卤代4,5-二芳基嘧啶和4,5-二芳基异恶唑。对联芳基偶联方法的比较研究提供了两个高效,互补的程序来完成最后的偶联步骤:分子内的Stille-Kelly卤代二芳基嘧啶和二芳基异恶唑的甲锡烷基化/偶联,以及相应非磷酸酯基的PIFA介导的非酚氧化偶联卤化的底物。此外,还研究了针对相同目标四环系统的其他替代方法。
A Combination of Tandem Amine-Exchange/Heterocyclization and Biaryl Coupling Reactions for the Straightforward Preparation of Phenanthro[9,10-<i>d</i>]pyrazoles
The tandem amine-exchange/heterocyclization of enaminoketones is successfully applied to the regioselective preparation of a series of new 4,5-diarylpyrazoles by reaction of phenylhydrazine and several 3-N,N-(dimethylamino)-1,2-diarylpropenones. The comparison of a vast array of biaryl coupling procedures provides general, complementary approaches to new phenanthro[9,10-d]pyrazoles. The most efficient
A Convenient One-Pot Preparative Method for 4,5-Diarylisoxazoles Involving Amine Exchange Reactions
作者:Esther Domínguez、Estíbaliz Ibeas、Eduardo Martínez de Marigorta、Jon Kepa Palacios、Raul SanMartín
DOI:10.1021/jo960024h
日期:1996.1.1
4,5-Diarylisoxazoles 1 are efficiently prepared by submitting enaminones 2, readily obtained from deoxybenzoins 3, to oximation conditions. This conversion implies an uncommon amine group exchange reaction. Preparation of 4-isoxazolines 5 and ring-opening transformations to beta-keto nitriles 4 and 1,3-amino alcohol derivatives 7 are also described.
SanMartin Raul, Marigorta Eduardo Martinez de, Dominguez Esther, Tetrahedron, 50 (1994) N 7, S 2255-2264
作者:SanMartin Raul, Marigorta Eduardo Martinez de, Dominguez Esther