N-Heterocyclic Carbene/Pd(OAc)2 Catalyzed Heck Coupling in Aqueous Medium

Abstract

In this study, novel 4-phenoxybutyl-substituted benzimidazolium salts as N-heterocyclic carbene (NHC) ligands were successfully synthesized and their structures characterized by 1H NMR, 13C NMR, FT-IR, and elemental analysis techniques. The in situ formed catalytic system using the NHC ligands and Pd(OAc)2 was used in the Heck coupling reactions between aryl bromides and strene with potassium carbonate in water/DMF mixture. The corresponding coupling products were obtained in high yields.

Keywords

• N-Heterocyclic carbene,C-C cross-coupling reactions,Heck coupling

Sulu Ortamda N-Heterosiklik Karben/Pd(OAc)2 Katalizli Heck C-C Eşleşmesi

Abstract

Bu çalışmada, N-heterosiklik karben (NHC) ligandı olarak yeni 4-fenoksibütil sübstitüyentli benzimidazolyum tuzları sentezlendi ve yapıları 1H NMR, 13C NMR, FT-IR ve element analizi yöntemleri ile karakterize edildi. Pd(OAc)2 ve NHC ligandları kullanılarak in situ oluşturulan katalitik sistem, su/DMF karışımında, potasyum karbonat varlığında stiren ve aril bromürlerin Heck eşleşme tepkimelerinde kullanıldı. Eşleşme ürünleri yüksek dönüşüm oranlarında elde edildi.

Keywords

• N-Heterosiklik karben,C-C çapraz eşleşme tepkimeleri,C-C çapraz eşleşme tepkimeleri,Heck eşleşmesi

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