Copper-doped silica cuprous sulfate (CDSCS) as a highly efficient heterogeneous nano catalyst for synthesis of 3,5-disubstituted isoxazoles
作者:M. N. Soltani Rad、S. Behrouz、M. A. Faghihi
DOI:10.1007/s13738-013-0307-4
日期:2014.4
A facile and highly efficient protocol for 1,3-dipolar cycloaddition of in situ generated nitrile oxides with terminal alkynes catalyzed by copper-doped silica cuprous sulfate (CDSCS) as a new and convenient heterogeneous nano catalyst is described. In this protocol, ‘click’ cycloaddition of various structurally diverse alkynes and imidoyl chlorides in the presence of CDSCS and NaHCO3 in a solution of i-PrOH/H2O (1:1, V/V) furnishes the corresponding 3,5-disubstituted isoxazoles in good to excellent yields at room temperature. CDSCS was approved as a chemically and thermally stable nano catalyst that can be recovered and reused for many consecutive trials without considerable decline in its reactivity.
A convenient, “one-pot” synthesis of trisubstituted pyrroles via a Ru(II)-catalyzed, Cu(II)-mediated reaction of substituted isoxazoles with sulfonylhydrazones has been developed. A series of highly functionalized pyrroles are obtained via a synergistic formation of new C−C and C−N bonds. Mechanistic investigations were carried out to propose the plausible pathway. This protocol provides a facile and
通过Ru( II ) 催化的、Cu( II ) 介导的取代异恶唑与磺酰腙的反应,一种方便的“一锅法”合成三取代吡咯得到了开发。通过新的 C-C 和 C-N 键的协同形成,获得了一系列高度功能化的吡咯。进行了机制研究以提出合理的途径。该协议为合成各种带有吡咯骨架的杂环化合物提供了一种简便快捷的方法。