DINITROGENVANADATES(-I) - SYNTHESIS, REACTIONS AND CONDITIONS FOR THEIR STABILITY
DINITROGENVANADATES(-I) - SYNTHESIS, REACTIONS AND CONDITIONS FOR THEIR STABILITY
复制标题
DOI：
10.1039/dt9940003471
复制
发表时间：
1994-12-07
期刊：
影响因子：
--
通讯作者：
REHDER, D
中科院分区：
文献类型：
--
作者：
GAILUS, H;WOITHA, C;REHDER, D
在膦 (L(m)) 和 N-2 存在下，用 Na 或 Li (M) 还原 [VCl3(thf)(3)] 生成配合物 Na[V(N-2)(n)(PMe(2)Ph)(6-n)] (n = 1 或 2)、M[V(N-2)(n)L(4-n)(2)] [n = 1 或 2, L(2) = Me(2)PCH(2)CH(2)-PMe(2) (dmpe) 或 Ph(2)PCH(2)CH(2)PPh(2)]、Na[V(N-2)(dmpe)L(3)] {L(3) = PhP[(CH2)(2)PPh(2)](2)、MeP[(CH2)(3)PMe(2)](2) (bdmpm) 或MeP[(CH2)(3)PEt(2)](2)} 和 Na[V(N-2)(2)L(4)] {L(4) = P[(CH2)(2)PPh(2)](3)、P[(CH2)(3)PMe(2)](3) 或 P[(CH2)(3)PEt(2)](3)}。一般来说，复合物是不稳定的，顺式和反式 M[V(N-2)(2)(dmpe)(2)] 具有最大稳定性。在 CO 或 CNBu(t) 存在下，N-2 被这些配体取代。这些化合物已通过 v(NN) 模式以及 V-51、Na-23 和 Li-7 NMR 光谱进行了表征。V-51 NMR 光谱显示出良好解析的多重峰。所有光谱数据，特别是四氢呋喃中顺式和反式[Li(thf)(x)][V(N-2)(2)(dmpe)(2)]的Li-7 NMR，都表明V-N=N ... M(+)类型的紧密接触离子对相互作用。钾离子和大阳离子如[NEt(4)](+)不能提供稳定的络合物，冠醚与Li+和Na+的络合导致N-2络合物立即分解。部分配位 N-2 到 NH4+（加上少量 N2H5+）的还原质子化根据与类似复合物的相似反应性特征以及这些 N-2 复合物作为固氮酶的功能模型的背景进行了讨论。化合物[V-2(bdmpm)(2)Cl-3]是VCl3 还原反应的中间产物，与LiNHNH2 反应生成氨。
Reduction of [VCl3(thf)(3)] by Na or Li (M) in the presence of phosphines (L(m)) and N-2 yielded the complexes Na[V(N-2)(n)(PMe(2)Ph)(6-n)] (n = 1 or 2), M[V(N-2)(n)L(4-n)(2)] [n = 1 or 2, L(2) = Me(2)PCH(2)CH(2)-PMe(2) (dmpe) or Ph(2)PCH(2)CH(2)PPh(2)], Na[V(N-2)(dmpe)L(3)] {L(3) = PhP[(CH2)(2)PPh(2)](2), MeP[(CH2)(3)PMe(2)](2) (bdmpm) or MeP[(CH2)(3)PEt(2)](2)} and Na[V(N-2)(2)L(4)] {L(4) = P[(CH2)(2)PPh(2)](3), P[(CH2)(3)PMe(2)](3) or P[(CH2)(3)PEt(2)](3)}. Generally, the complexes are labile, with a maximum stability for cis- and trans-M[V(N-2)(2)(dmpe)(2)]. In the presence of CO or CNBu(t), N-2 is replaced by these ligands. The compounds have been characterized by their v(NN) pattern and by V-51, Na-23 and Li-7 NMR spectroscopy The V-51 NMR spectra exhibit well resolved multiplets. All spectroscopic data, in particular Li-7 NMR of cis-and trans-[Li(thf)(x)][V(N-2)(2)(dmpe)(2)] in tetrahydrofuran, are indicative of close contact ion-pair interaction of the kind V-N=N ... M(+). The potassium ion and large cations such as [NEt(4)](+) do not provide stable complexes, and complexation of Li+ and Na+ by crown ethers leads to immediate decomposition of the N-2 complexes. The reductive protonation of part of the co-ordinated N-2 to NH4+ (plus small amounts of N2H5+) is discussed in terms of similar reactivity features to the analogous complexes, and in the context of these N-2 complexes as functional models for nitrogenases. The compound [V-2(bdmpm)(2)Cl-3], isolated as an intermediate product of the reduction of VCl3 reacted with LiNHNH2 to yield ammonia.