Facile one-pot nanocatalysts encapsulation of palladium–NHC complexes for aqueous Suzuki–Miyaura couplings. (28th February 2018)

• Record Type: Journal Article
• Authors: Chen, Chao; Zheng, Qing; Ni, Shengliang; Wang, Hangxiang
• Is Part Of: New journal of chemistry. Volume 42:Number 6(2018)
• Page Start: 4624
• Page End: 4630
• Publication Date: 2018-02-28
• Subjects: Chemistry -- Periodicals; Chimie -- Périodiques; 540
• DOI: 10.1039/c7nj04836j
• Languages: English
• ISSNs: 1144-0546

Abstract

Abstract : Pd–NHC loaded nanocatalysts (NCs) were readily constructed by a facile one-pot self-assembly approach. These nanoparticles exhibited excellent catalytic activity in aqueous Suzuki–Miyaura couplings. Abstract : Organic transformations using water as the solvent have been the focus of intense investigation. We herein present a strategy that uses simple nanoparticle encapsulation to fabricate water-soluble nanocatalysts (NCs) for aqueous cross-coupling reactions. To achieve this goal, three types of N-heterocyclic carbene (NHC)–palladium (Pd) complexes ( i.e., 1b, 2b, and3b ) with the chemical formula [PdL(CH3 CN)Cl]PF6 (where L is a bidentate pyridine- or pyrimidine-bearing NHC ligand) have been synthesized, and their structures were characterized by NMR spectroscopy and X-ray crystallography. Exploiting a facile one-pot encapsulation process, the water-insoluble Pd–NHC complexes can be integrated into the hydrophobic cores of micelles composed of an amphiphilic copolymer. These water-dispersed nanoparticles exhibited excellent catalytic activity in aqueous Suzuki–Miyaura couplings. Among these NCs, 3b -NC, bearing a mesityl moiety on its NHC ligand, was found to be the most active catalyst under the tested reaction conditions. More impressively, 3b -NC can be reused for at least five cycles without substantial loss of catalytic activity.