| Summary: | 碩士 === 國立清華大學 === 化學系 === 92 === Reaction of Ni(ClO4)2．6H2O with 1 equiv. of P(o-C6H4SH)3 in THF leads to the formation of a dimeric complex, Ni2{P(o-C6H4S)2(o-C6H4SH)}2 (1). Complex 1 contains distorted square planar, diamagnetic Ni(II) centers ligated by a phosphorus, a terminal thiolate, two thiolates that bridge to the second Ni, and a S-H proton directly interacting with both nickel and sulfur atoms. The presence of combination of intramolecular [Ni-S…H-S] /[Ni…H-S] interactions was verified in the solid state by the observation of IR νSH stretching band (2391cm-1), 1H NMR (δ5.880(s) in CDCl3) and subsequently confirmed by X-ray diffraction study. Isolation and characterization of complex 1 may reflect the existence of Ni-R/Ni-SIa atates as [(Scys-H)Ni(Scys)3Fe] corrdination environment in [NiFe] hydrogenase. Reaction of Ni(ClO4)2．6H2O with 2 equiv. of P(o-C6H4SH)3 in THF results in the formation of mononuclear and square planar complex, Ni{P(o-C6H4S)(o-C6H4SH)2}2 (3) with four S-H protons, where Nickel is coordinated by two sulfurs and two phosphorus. X-ray diffraction study indicate that two bulky ligands, {P(o-C6H4S)(o-C6H4SH)2}, keeps S-H proton away from nickel and sulfur atoms and there were weak intramolecular [Ni-S…H-S] /[Ni…H-S] interactions in complex 3. The thiol proton in complex 1 and 3 was easily removed by Lewis base Et3N to yield the known Ni(II) dimer [NiII(P(o-C6H4S)3)]22- (2).
The hexacoordinate Fe(II) complex [PPN][Fe(CO)2(CN)(S,NH2-C6H4)(S-C6H4NH2) (5) was prepared by the reaction of 2-aminophenyl disulfide and [PPN][Fe(CO)4(CN)]. Upon contact with dry O2, or treated with Lewis base Et3N, complex 5 turned to the pentacoordinate Fe(II) complex [PPN][Fe(CO)2(CN)(S,NH-C6H4)] (6).
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