An efficient recyclable polymer-supported bis-quaternary onium phase-transfer catalyst for the synthesis of dihalocyclopropyl derivatives at low alkaline concentration-comparative kinetic aspects
In this work, a new polystyrene-bound bis-onium phase-transfer catalyst was synthesized, and their catalytic activities were investigated in the synthesis of dichlorocyclopropyl derivatives of olefins. The new polymer-anchored multi-site phase-transfer catalyst showed significant high catalytic activity as compared to single-site phase-transfer catalyst. The comparative kinetic investigation reveals that the dichlorocyclopropanation of 1-methyl-4-vinyl benzene is faster than styrene in the presence of the new catalyst. This catalyst can be used several times with consistent catalytic activity. Experimental observations support an interfacial-type mechanism. Furthermore, its catalytic utility was examined in alkylation reactions.
Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► A novel polymer-supported bis-onium salt is synthesized. ► Bis-onium salt catalyzed comparative dichlorocyclopropanation is developed. ► New catalyst is highly active than conventional single-site onium salts. ► Recycle study is encouraging.
Journal: Catalysis Communications - Volume 22, 10 May 2012, Pages 6–12