Preparation of palladium(II) complexes with long alkyl chain ligand incorporated in micelle

Abstract

Three palladium(II) complexes with a bidentate nitrogen ligand having a long alkyl chain (1, [PdCl2(C8-tmen)], C8-tmen=N,N,N′-trimethyl-N′-octylethylenediamine; 2, [PdCl2(C16-tmen)], C16-tmen=N,N,N′-trimethyl-N′-cetylethylenediamine; 3, [PdCl2(C8-bpy)], C8-bpy=4-octyl-2,2′-bipyridine) were prepared. Addition of 1 to an aqueous solution of cetyltrimethylammonium bromide gave a metallomicelle containing the Pd(II) complex (1A). The other palladium complexes (2 and 3) were not incorporated into the CTABr micelle due to the unsuitable matching between the ligand and the micelle. 1A showed good catalytic performance for Suzuki and Heck coupling reactions in water. The catalyst system for the Heck reaction in water was reusable.