Organic-soluble optically pure anionic metal complexes PPh4[MIII(S,S-EDDS)]·2H2O (M = Fe, Co, Cr)
作者:Nikola Paul Chmel、Suzanne E. Howson、Laura E. N. Allan、James Barker、Guy J. Clarkson、Scott S. Turner、Peter Scott
DOI:10.1039/b924787d
日期:——
The first organic-soluble, optically and diastereomerically pure EDDS metal complexes have been synthesised. A number of synthetic approaches were attempted, but finally the tetraphenylphosphonium series emerged as providing readily accessible compounds of trivalent Cr, Fe and Co in reasonable yields via the silver salts without the need to perform ion-exchange chromatography. The species PPh4[MIII(S,S-EDDS)] are very soluble in methanol, acetonitrile and even THF but isolation was facilitated by addition of stoichiometric water giving the highly crystalline but still conveniently soluble title compounds. The structures of the three isomorphous crystals comprise H2O-bridged extended hydrogen bonded structures with large channels occupied by the counterion molecules. The magnetic properties and circular dichroism spectra are reported along with comparative data for water-soluble NH4[FeIII(S,S-EDDS)]. Phase purity (and hence diastereomeric purity) in the paramagnetic systems is assessed through powder XRD. The practical utility of this type of compound was confirmed by optical resolution of (±)-[RuII(bpy)3]Cl2.
首次合成了有机溶解的、光学和立体异构体纯的EDDS金属复合物。尝试了多种合成方法,最终四苯基磷系列被发现可通过银盐在合理的产率下方便地获得三价铬、铁和钴的化合物,而无需进行离子交换色谱。化合物PPh4[MIII(S,S-EDDS)]在甲醇、乙腈甚至四氢呋喃中具有很高的溶解度,但通过加入化学计量的水来促进分离,从而得到高度结晶但仍然方便溶解的标题化合物。这三种同晶型晶体的结构由H2O桥接的扩展氢键结构组成,具有大的通道,里面被对离子分子占据。报告了其磁性质和圆二色性光谱,并提供了可溶于水的NH4[FeIII(S,S-EDDS)]的比较数据。通过粉末XRD评估了该类参数磁性体系的相纯度(因此也是立体异构体纯度)。通过对(±)-[RuII(bpy)3]Cl2的光学分离,确认了这种化合物的实际应用价值。