title: Synthesis of [PdL(NH3)2](PF6)2 (L = 1,1'-di(alkyl)-3,3'-methylenediimidazolin-2,2'-diylidene) complexes and their reactivities towards N-donors.
abstract: The reaction of neutral palladium complexes PdLBr2 (L = 1,1′-di(alkyl)-3,3′-methylenediimidazolin-2,2′-diylidene) with NH4PF6 in CH3CN afforded [PdL(NH3)2](PF6)2 (1–3, L1, alkyl = Me; L2, alkyl = Et; L3, alkyl = iso-Pr) and [PdL4(CH3CN)2](PF6)2 (4, alkyl = Mes). Treatment of [PdL(NH3)2](PF6)2 complexes with N-donors, 9-ethyl-3,6-diimidazolyl-carbazole (dicz), mercaptopyridine (HSPy), 3,5-dimethyl-1H-pyrazole (Hdmpz), and 1,2-dibenzoylhydrazine (H2dbhz) resulted in the substitution of NH3 forming dinuclear palladium complexes [PdL1(dicz)]2(PF6)4 (5), [PdL1(SPy)]2(PF6)2 (6), [PdL2(dmpz)]2(PF6)2 (7), [(PdL2)2(dbhz)] (8). Reaction of [PdL2(NH3)2](PF6)2 with hydrazine led to a mixture of [Pd(L2)2](PF6)2 (9) and [PdL2(NH2N=C(CH3)NHNH2)](PF6)2 (10). The NH2N=C(CH3)NHNH2 moiety was formed in situ by nucleophilic addition to CH3CN by two molecules of NH2NH2 and subsequent NH3 elimination. All of these complexes have been fully characterized by ESI-MS, NMR spectroscopy, and elemental analysis. The molecular structures of 1 and 5–10 were also studied by X-ray diffraction analysis.
authors.affiliation: Department of Chemistry, Zhejiang University, Xixi Campus, Hangzhou 310028, People's Republic of China.
authors.forename: Chao
authors.initials: C
authors.lastname: Chen
authors.forename: Wanzhi
authors.initials: W
authors.lastname: Chen
authors.forename: Huayu
authors.initials: H
authors.lastname: Qiu