Application of Fe3O4@SiO2@sulfamic acid magnetic nanoparticles as recyclable heterogeneous catalyst for the synthesis of imine and pyrazole derivatives in aqueous medium
作者:B. Zakerinasab、M. A. Nasseri、H. Hassani、M. M. Samieadel
DOI:10.1007/s11164-015-2204-1
日期:2016.4
Sulfamic acid supported on Fe3O4@SiO2 superpara magnetic nanoparticles was successfully applied as a recyclable solid acid catalyst with a large density of sulfamic acid groups for the synthesis of pyrazole derivatives, an important class of potentially bioactive compounds. The products are obtained in high yield from the one-pot reaction procedure involving dicarbonyl compounds and hydrazines/hydrazides. This new method totally avoids the use of toxic or expensive solvents and organic acids in this reaction.
PEG–SO3H as a mild, efficient and green catalytic system for the synthesis of pyrazole derivatives in aqueous medium
作者:M. A. Nasseri、S. A. Alavi、B. Zakeri Nasab
DOI:10.1007/s13738-012-0143-y
日期:2013.4
A versatile, alternative and environmentally benign strategy for the synthesis of a series of pyrazoles has been successfully performed in water using PEG–SO3H as an acidic catalyst. The products are obtained in high yield from the one-pot reaction procedure involving dicarbonyl compounds and hydrazines/hydrazides. This new method totally avoids the use of organic acids and toxic or expensive solvents in this reaction. The catalyst is waste-free, easily prepared, and efficiently re-used.
Cellulose sulfuric acid as a bio-supported and efficient solid acid catalyst for synthesis of pyrazoles in aqueous medium
作者:Mohammad Ali Nasseri、Mehri Salimi、Abbas Ali Esmaeili
DOI:10.1039/c4ra11440j
日期:——
A convenient and practical method was described for the regioselective synthesis of pyrazoles from hydrazines/hydrazides and 1,3-dicarbonyl compounds via the Knorr synthesis in water with cellulose sulfuricacid (CSA) as a biopolymer-based solidacidcatalyst. Various hydrazines and hydrazides were reacted with 1,3 diketones and the desired pyrazoles were obtained in high yields. The reaction of less
Magnetic Nanoparticle-Supported Glutathione as a Sustainable Organocatalyst
申请人:Varma Rajender S.
公开号:US20110054180A1
公开(公告)日:2011-03-03
This invention relates to the use of nano-organocatalysts, and, more specifically, to the use of magnetic nanomaterial-supported organocatalysts. It is an object of the present invention to provide “green” catalysts and protocols. According to one embodiment of the invention, a nano-organocatalyst in the form of a magnetic nanomaterial-supported organocatalyst is provided. According to other embodiments of the invention, glutathione and cysteine are provided as organocatalysts and magnetic nanomaterial-supported glutathione and magnetic nanomaterial-supported cysteine are provided for use as nano-organocatalysts. According to another embodiment of the invention, a method of using a recyclable magnetic nanomaterial-supported organocatalyst using a totally benign aqueous protocol, without using any organic solvent in the reaction or during the workup, is provided. According to a further embodiment of the invention, a recyclable magnetic nanomaterial-supported organocatalyst for various organocatalytic reactions, including but not limited to Paal-Knorr reactions, aza-Michael addition and pyrazole synthesis, is provided.
Nano-organocatalyst: magnetically retrievable ferrite-anchored glutathione for microwave-assisted Paal–Knorr reaction, aza-Michael addition, and pyrazole synthesis
作者:Vivek Polshettiwar、Rajender S. Varma
DOI:10.1016/j.tet.2009.11.015
日期:2010.1
Postsynthetic Surface modification of magnetic nanoparticles by glutathione imparts desirable chemical functionality and enables the generation of catalytic sites on the surfaces of ensuing organocatalysts. In this article, we discuss the developments, unique activity, and high selectivity of nano-organocatalysts for microwave-assisted Paal-Knorr reaction, aza-Michael addition, and pyrazole synthesis. Their insoluble character Coupled with paramagnetic nature enables easy separation of these nano-catalysts from the reaction mixture using external magnet, which eliminates the requirement of catalyst filtration. Published by Elsevier Ltd.