| Summary: | Commercially available substrates for the synthesis of chiral bidentate phosphinothiolate and phosphinothioether ligands are usually limited with low molecular weights. We report the synthesis of two sterically diverse ligands and how their backbones can influence reactivity and coordination geometries. Phosphinothiol ligand 2-(diphenylphosphino)cyclohexanethiol (L1!!) has been successfully synthesised using commercially available cyclohexene sulphide and fully characterised. A second chiral bidentate phosphinothiolate ligand 9, 10-ethanoanthracene-2-diphenylphosphino-1-ethanethiol, 9-10-dihydro, (L2H) has been synthesised via a seven step process derived from anthracene. A series of phosphinothioether ligands have been synthesised using the phosphinothiolate LJLi and L2K precursors. The series includes thioether moieties containing benzyl (L*Bn, L2Bn), 1-methyl naphthalene (Ll-MN, L21-MN) and 9-methyl anthracene (L-MAN, L29-MAN). L/H reacts with divalent nickel and palladium to form complexes of general formula MCL1): (7, M=Ni), (8, M=Pd), M(L1)C1 2 (9. M=Ni) and MCLMCb (11, M=Pd). We also report the formation of a novel dimer complex using the well researched 2-(diphenylphosphino)ethanethiol (dppet) ligand, M(dppet)Cl 2 (10, M=Pd). We report the first structural characterisation of a nickel phosphinothiolate bis-chelate and dimer complexes. L2H reacts with divalent palladium to produce a number of polymeric complexes M(L2)2 (12, M=Pd), M(L2S02)2 (13, M=Pd) M (L2)C1 2 (14, M=Pd) MCl2 Pd(L2)2M(H20)Cl2 2 (15, M=Pd) M (L1)C1 3 (16. M=Pd). Complexes are structurally analysed via their crystallographic data and compared. Complexation of phosphinothioether ligands using divalent nickel and palladium yield the following dihalide complexes M(L1Bn)Br2 (17, M=Ni). (18, M=Pd), MCl/BiCh (19, M=Ni), (20, M=Pd), MOl-MNlo (21, M=Pd), M(1-MNL11- MN)C12 (22, M=Pd), M(L19-MAN)C12 (23, M=Pd). The resulting complexes are structurally compared to similar complexes reported in the literature. We report a similar series of phosphinothioether ligands as previously described using the phosphinothiolate precursor L2K. Complexation of these ligands with divalent palladium resulted in the corresponding dichloride complexes Pd(L2Bn)Cl2 (24), Pd(L2l-MN)Cl2 (26) and Pd(L29-MAN)Cl2 (28). NMR analysis revealed the complexes were fluxional between conformations and diastereoisomers at room temperature. Variable temperature NMR studies show the relative intensities of the inter-converting species. Finally the series of phosphinothioether ligands were coordinated using iridium cod chloride dimer to form complexes: Ir(L Bn)(cod) (25), Ir(L l-MN)(cod) (27) and Ir(L29-MAN)(cod) (29).
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