Proceeding from 4-heteryl-2,4-dioxobutanoic acids were prepared (Z)-3-heteroylmethylene1,2,3,4-tetrahydro-2-quinoxalones that when treated with oxalyl chloride afforded 3-heteroyl-1,2,4,5-tetrahydropyrrolo[1,2-a]quinoxaline-1,2,4-triones. The latter took in reactions with o-aminophenol and o-phenylenediamine two different directions.
A combination of heterogeneous catalysis and photocatalysis for the olefination of quinoxalin-2(1<i>H</i>)-ones with ketones in water: a green and efficient route to (<i>Z</i>)-enaminones
features very mild conditions using a simple and cheap catalyst for the synthesis of (Z)-enaminones with moderate-to-good yields. Such a methodology successfully combines the heterogeneous Mannich reaction with photocatalysis, and provides a green and practical approach for the synthesis of potentially bioactive (Z)-enaminones with a 3,4-dihydroquinoxalin-2(1H)-one skeleton.
Formation of 4-(het)aryl-3H-1,5-benzodiazepine-2-carboxylates from (het)aroylpyruvate esters and o-phenylenediamine
作者:Ekaterina E. Khramtsova、Maksim V. Dmitriev、Andrey N. Maslivets
DOI:10.1007/s10593-023-03235-6
日期:2023.8
Esters of (het)aroylpyruvic acids can react with o-phenylenediamine, leading to the formation of (Z)-3-(2-(het)aryl-2-oxoethylidene)-3,4-dihydroquinoxalin-2(1H)-ones and 4-(het)aryl-3H-1,5-benzodiazepine-2-carboxylates. The obtained product ratio depends on the electronic effects due to substituents in the (het)aroyl moiety of (het)aroylpyruvate esters and the reaction conditions. The highest ratio
(杂)芳酰基丙酮酸的酯可以与邻苯二胺反应,导致形成 ( Z )-3-(2-(杂)芳基-2-氧代亚乙基)-3,4-二氢喹喔啉-2(1 H )-和4-(杂)芳基-3H- 1,5-苯二氮卓-2-羧酸酯。所获得的产物比率取决于由于(杂)芳酰基丙酮酸酯的(杂)芳酰基部分中的取代基所产生的电子效应和反应条件。当使用不带取代基的(杂)芳酰基丙酮酸酯时,以及在乙酸中进行反应时,观察到与药物化学相关的喹喔啉酮的最高比例,取代基会导致(杂)芳酰基部分产生负面介观效应。