新的cis—Pt(diphos)(Ⅹ)_2配合物的合成和谱学表征

SYNTHESES AND CHARACTERISATION OF NEW C/S-Pt(DIPHOS)X_2 COMPLEXES

本文合成了三个新的双膦螯合配体和一系列新的cis-Pt(diphos)X_2(diphos=R_2PCH_2CH_2PR_2,R=Et,n-Pr,n-Bu,i-Bu;X=Cl^-,Br^-,I^-,CN^-,SCN^-,NO_2^-)配合物,经过IR、^(31)PNMR和元素分析表征了它们的结构,并观察到^(31)P化学位移δp、铂-磷偶合常数J(p1-p)与配体X的反位效应和双膦配体的σ-供电性质有关。此外,根据谱学研究,发现SCN^-和NO_2^-配体存在键合异构现象,并对谱带进行了归属。

A series of new Pt(II) complexes of bis(dialkylphosphino) ethane were synthesized and characterized by IR, 31PNMR and elemental analyses. The general formula of these complexes is as follows: R=CH3CH2-,depe; CH3CH2CH2-, d(n-Pr)pe; CH3CH2CH2CH2-, d(n-Bu)pe; (CH3)2CH-, d(i-Pr)pe;(CH3)2CHCH2-,d(i-Bu)pe. X = CF, Br-, I-, CN-, SCN-, NO2. The magnitudes of 31P chemical shifts δP and platinum-phosphorus coupling constants 1Jpt-p are correlatea with the electro-donating capability of the diphosphine ligands and the trans effect of the anionic ligands X. The coupling con star+s 1Jpt-p, on the one hand, should decrease as the diphosphine ligands in the order of d(i-Pr)pe > depe > d(n-Bu)pe > d(n-Pr)pe > d(i-Bu)pe, and on the other hand, it should increase as the trans-effect of the ligands X decreases in the order of CN->NO2->SCN->NCS->r>Br->Cr>ONO-. Further, we have also observed the linkage isomeres of thiocyanato-platinum(e.g. Pt-SCN) and isothiocyanato-platinum(e.g. Pt-NCS), nitroplatinum (e.g. Pt-NO2) and nitrito-platinum(e.g. Pt-ONO), and made assign-ments by means of IR and 31P NMR spectroscopies.