PYRIDINE AND PYRAZINE ADDUCTS OF TETRAKIS(ACETATO)DICHROMIUM
PYRIDINE AND PYRAZINE ADDUCTS OF TETRAKIS(ACETATO)DICHROMIUM
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DOI：
10.1021/ic50204a011
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发表时间：
1980-01-01
影响因子：
4.6
通讯作者：
FELTHOUSE, TR
中科院分区：
文献类型：
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作者：
COTTON, FA;FELTHOUSE, TR
吡啶和吡嗪分别与 Cr2 (OAc) 4 形成 2:1 和 1:1 加合物，已通过 X 射线晶体学表征。该结构与相应的铜 (II) 配合物是同晶的。 Cr2-(OAc) 4 (py) 2 (1) 晶体是斜方晶系，属于 Pbca 空间群，晶胞尺寸为 a= 13.055 (2) Á、b= 8.645 (1) A、c= 19.560 (3) Á 和 V= 2207.5 (6) A3。通过 I> 3 () 的 891 次反射对结构进行细化，最终差异指数为 R¡= 0.060 和 R2= 0.081。该结构由中心对称式单元组成，Cr-Cr键长为2.369(2)μ，Cr-N键长为2.335(5)μ。吡嗪 (pyz) 加合物 Cr2 (OAc) 4 (pyz)(2) 在空间群 C2/m 中结晶，其中 a= 7.979 (2) Á、b= 14.350 (4) Á、c= 7.376 (2) Á、ß= 101.78 (2)、V= 826.7 (4) A3 和 Z= 2。通过使用 365 度反射来求解结构 其中 I> 2 () 得到 R {= 0.065 且 R2= 0.079 的最终残差。 Cr2(OAc) 4 单元中的Cr-Cr键长为2.295(5)μ，这些中心对称单元通过CN键长为2.31(1)μ的吡嗪分子连接成直链。
Pyridine and pyrazine form 2: 1 and 1: 1 adducts, respectively, with Cr2 (OAc) 4 which have been characterized by X-ray crystallography. The structures are isomorphous to those of the corresponding copper (II) complexes. Crystals of Cr2-(OAc) 4 (py) 2 (1) are orthorhombic and belong to space group Pbca with fourmolecules in a unit cell of dimensions a= 13.055 (2) Á, b= 8.645 (1) A, c= 19.560 (3) Á, and V= 2207.5 (6) A3. The structure was refined with 891 reflections having I> 3 () to final discrepancy indices of R¡= 0.060 and R2= 0.081. The structure consists of centrosymmetric formula units with a Cr-Cr bond length of 2.369 (2) Á and a Cr-N bond length of 2.335 (5) Á. The pyrazine (pyz) adduct, Cr2 (OAc) 4 (pyz)(2), crystallizes in the space group C2/m with a= 7.979 (2) Á, b= 14.350 (4) Á, c= 7.376 (2) Á, ß= 101.78 (2), V= 826.7 (4) A3, and Z= 2. The structure was solved by using 365 reflections with I> 2 () to give final residuals of R {= 0.065 and R2= 0.079. The Cr-Cr bond length in the Cr2 (OAc) 4 units is 2.295 (5) Á and these centrosymmetric units are linked into linear chains by the pyrazine molecules with CN bond lengths of 2.31 (1) Á.