A low melting citric acid-urea mixture was found to be a new and effective promoting medium for the environmentally friendly synthesis of 1,8-dioxo-dodecahydroxanthene derivatives by condensation of aromatic alde-hyde...A low melting citric acid-urea mixture was found to be a new and effective promoting medium for the environmentally friendly synthesis of 1,8-dioxo-dodecahydroxanthene derivatives by condensation of aromatic alde-hydes and cyclic 1,3-dicarbobonyl compounds. This deep eutectic solvent acts as both the reaction medium and catalyst, furnishing xanthenediones in high to excellent yields.展开更多
A simple, facile and convenient strategy has been developed for the synthesis of dihydropyrimidine-5-carbox-amides in low melting mixture of betaine hydrochloride/urea. In this procedure, the low melting mixture of be...A simple, facile and convenient strategy has been developed for the synthesis of dihydropyrimidine-5-carbox-amides in low melting mixture of betaine hydrochloride/urea. In this procedure, the low melting mixture of betaine hydrochloride/urea plays a triple role： as a catalyst, solvent and reactant. The present green protocol has advantages such as high yield of products, short reaction times, operational simplicity, no chromatographic separation, eco-friendliness, and applicability for large-scale synthesis.展开更多
基金This work was financially supported by the National Natural Science Foundation of China，the Nature Science Foundation of Hebei Province
文摘A low melting citric acid-urea mixture was found to be a new and effective promoting medium for the environmentally friendly synthesis of 1,8-dioxo-dodecahydroxanthene derivatives by condensation of aromatic alde-hydes and cyclic 1,3-dicarbobonyl compounds. This deep eutectic solvent acts as both the reaction medium and catalyst, furnishing xanthenediones in high to excellent yields.
文摘A simple, facile and convenient strategy has been developed for the synthesis of dihydropyrimidine-5-carbox-amides in low melting mixture of betaine hydrochloride/urea. In this procedure, the low melting mixture of betaine hydrochloride/urea plays a triple role： as a catalyst, solvent and reactant. The present green protocol has advantages such as high yield of products, short reaction times, operational simplicity, no chromatographic separation, eco-friendliness, and applicability for large-scale synthesis.
