1. Nickel(II) Complexes Containing Bidentate Diarylamido Phosphine Chelates: Kumada Couplings Kinetically Preferred to β-Hydrogen Elimination
- Author
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Ming-Tsz Chen, Lan-Chang Liang, Wei-Ying Lee, and Tzung-Ling Tsai
- Subjects
Denticity ,Organic Chemistry ,Inorganic chemistry ,Trimethylphosphine ,chemistry.chemical_element ,Medicinal chemistry ,Chloride ,Adduct ,Inorganic Chemistry ,Nickel ,chemistry.chemical_compound ,chemistry ,medicine ,Chelation ,Physical and Theoretical Chemistry ,Homoleptic ,Phosphine ,medicine.drug - Abstract
A series of divalent nickel complexes containing diarylamido phosphine ligands of the type (o-ArNC6H4PR2)− (1a, Ar = 2,6-C6H3Me2, R = Ph; 1b, Ar = 2,6-C6H3iPr2, R = Ph; 1c, Ar = 2,6-C6H3Me2, R = iPr; 1d, Ar = 2,6-C6H3iPr2, R = iPr) have been prepared and structurally characterized. The dimeric nickel chloride derivatives {[1b–d]Ni(μ-Cl)}2 (2b–d) were isolated as brick red microcrystals in high yields from the reactions of NiCl2(DME) with either Li[1b–d](solv)x or H[1b–d] in the presence of NEt3. Similar reactions employing [1a]−, however, generated homoleptic Ni[1a]2 (3a) as paramagnetic, dark red prisms in high yield. Addition of trimethylphosphine to red solutions of 2b,c in THF at room temperature afforded emerald crystals of [1b,c]NiCl(PMe3) (4b,c). Interestingly, solution NMR spectroscopic and X-ray crystallographic data of these PMe3 adducts reveal the exclusive formation of cis-4b and trans-4c, as defined by the mutual orientation of the two phosphorus donors incorporated. Metathetical reactions of...
- Published
- 2014