Is 2.07 Å a Record for the Shortest Pt-S Distance? Revision of Two Reported X-ray Structures
Is 2.07 Å a Record for the Shortest Pt-S Distance? Revision of Two Reported X-ray Structures
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DOI：
10.1021/ic8023748
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发表时间：
2009-04-20
影响因子：
4.6
通讯作者：
Mealli, Carlo
中科院分区：
文献类型：
--
作者：
Ienco, Andrea;Caporali, Maria;Mealli, Carlo
非常相似的化合物（Ph 3 P）（2）Pt（mu-S）（2）Pt（PPh 3）（2）（1）和（Ph 2 PyP）（2）Pt（mu-S）（2）Pt（PPh 2 Py）（2）（2）的比较提出了关于1中所报道的Pt 2S 2核的可靠性的有趣问题，其中Pt-S键是有史以来报道的最短的。此外，2.69埃的跨环S中心点中心点S间隔在1中令人惊讶地短于在2中（3.01埃），但是在这种情况下，两个S2桥之间没有初始耦合似乎是合理的。各种考虑导致将1重新配制为[（Ph 3 P）（2）Pt（μ-OH）（2）Pt（PPh 3）（2）]（BF 4）（2），3。1和3的单元参数集不相等，但两个轴匹配，并且1的体积正好是两倍。简单的矩阵可以被构造成使正向和倒向晶胞相互转换，从而证实它们的化合物的身份。它的结论是，在1的结构解决方案中，一些原子被忽略（BF 4-抗衡离子）或不好识别（硫代羟基桥的地方），而3的结构是通过收集只有一半的可能的反射（因此，也是不同的空间群）。3的新制备、结晶和X射线结构证实了上述观点，并驳回了关于1和2中两个电子不同的Pt 2S 2核的任何其他理论猜想。
The comparison of the very similar compounds (Ph3P)(2)Pt(mu-S)(2)Pt(PPh3)(2) (1) and (Ph2PyP)(2)Pt(mu-S)(2)Pt(PPh2Py)(2) (2) raises intriguing questions about the reliability of the reported Pt2S2 core in 1, where the Pt-S bonds are the shortest ever reported. Also, the trans-annular S center dot center dot center dot S separation of 2.69 angstrom is surprisingly shorter in 1 than in 2 (3.01 angstrom), but no incipient coupling between two S2- bridges seems reasonable in this case. Various considerations lead to reformulate 1 as [(Ph3P)(2)Pt(mu-OH)(2)Pt(PPh3)(2)](BF4)(2), 3. The sets of cell parameters for 1 and 3 are not equal but two axes match, and the volume of 1 is exactly double. Simple matrices may be constructed to interconvert the direct and reciprocal crystalline cells, thus corroborating their identity of the compounds. It is concluded that, in the structure solution of 1, some atoms were either neglected (BF4- counterions) or ill identified (sulfido in place of hydroxo bridges), while the structure of 3 was solved by collecting only one-half of the possible reflections (hence, also the different space groups). A new preparation, crystallization and X-ray structure of 3 confirms the above points and dismisses any other theoretical conjecture about two electronically different Pt2S2 cores in 1 and 2.