(RO)2P(S)SSP(S)(OR)2 (IIa: R = Et; IIb: R = i-Pr) and R2NC(S)SSC(S)NR2 (IIIa: R = Me; IIIb: R = Et) to give niobium complexes via SS bond cleavage of the organic substrates. With IIa and IIb, the paramagnetic niobium complexes [Nb(η5-C5H5)2PS2(OR)2}2] (IV) are obtained, while IIIa and IIIb give diamagnetic niobium(V) derivatives. EPR spectra of complexes IV have been recorded at 130 and 295 K and are analysed
[Nb的(η 5 -C 5 H ^ 5)2(CH 3)2 ](I)反应与(RO)2 P(S)S
SP(S)(OR)2(IIA:R =的Et; IIB: R = i-Pr)和R 2 NC(S)SSC(S)NR 2(IIIa:R = Me; IIIb:R = Et),通过有机底物的SS键裂解得到
铌配合物。与IIa和IIb,所述顺磁性
铌配合物[Nb的(η 5 -C 5 H ^ 5)2 PS 2(OR)2 } 2得到[IV],而IIIa和IIIb得到抗磁性的
铌(V)衍
生物。配合物IV的EPR光谱已在130和295 K处记录,并进行了详细分析。给出了自旋哈密顿量参数,并将其与参与键合的基态分子轨道中的原子轨道系数进行比较。他们表明:(i)未配对的电子基本上位于4 d x 2 - y 2
金属离子轨道中,并与少量相应的
金属离子4 d z 2轨道混合,z轴与C 2轴重合该化合物; (ii)除了在[
铌(η较弱的离域5