Yasmin Sabina, Suarez Sebastián, Doctorovich Fabio, Roy Tapashi G, Baggio Ricardo
University of Chittagong, Chittagong 4331, Bangladesh.
Acta Crystallogr C. 2013 Aug;69(Pt 8):862-7. doi: 10.1107/S0108270113018465. Epub 2013 Jul 20.
The three transition-metal complexes, (meso-5,7,7,12,14,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane-κ⁴N)bis(perchlorato-κO)copper(II), [Cu(ClO₄)₂(C₁₈H₄₀N₄)], (I), (meso-5,7,7,12,14,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane-κ⁴N)bis(nitrato-κO)zinc(II), [Zn(NO₃)₂(C₁₈H₄₀N₄)], (II), and aquachlorido(meso-5,7,7,12,14,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane-κ⁴N)copper(II) chloride, [CuCl(C₁₈H₄₀N₄)(H₂O)]Cl, (III), are described. The molecules display a very similarly distorted 4+2 octahedral environment for the cation [located at an inversion centre in (I) and (II)], defined by the macrocycle N₄ group in the equatorial sites and two further ligands in trans-axial positions [two O-ClO₃ ligands in (I), two O-NO₂ ligands in (II) and one chloride and one aqua ligand in (III)]. The most significant difference in molecular shape resides in these axial ligands, the effect of which on the intra- and intermolecular hydrogen bonding is discussed. In the case of (I), all strong hydrogen-bond donors are saturated in intramolecular interactions, while weak intermolecular C-H∙∙∙O contacts result in a three-dimensional network. In (II) and (III), instead, there are N-H and O-H donors left over for intermolecular interactions, giving rise to the formation of strongly linked but weakly interacting chains.
（内消旋-5,7,7,12,14,14-六甲基-1,4,8,11-四氮杂环十四烷-κ⁴N）双（高氯酸根-κO）铜（II），[Cu(ClO₄)₂(C₁₈H₄₀N₄)]，（I）；（内消旋-5,7,7,12,14,14-六甲基-1,4,8,11-四氮杂环十四烷-κ⁴N）双（硝酸根-κO）锌（II），[Zn(NO₃)₂(C₁₈H₄₀N₄)]，（II）；以及水合氯（内消旋-5,7,7,12,14,14-六甲基-1,4,8,11-四氮杂环十四烷-κ⁴N）铜（II）氯化物，[CuCl(C₁₈H₄₀N₄)(H₂O)]Cl，（III）。这些分子对于阳离子[位于（I）和（II）的对称中心]呈现出非常相似的扭曲4+2八面体环境，该环境由位于赤道位置的大环N₄基团以及处于反式轴向位置的另外两个配体定义[（I）中的两个O-ClO₃配体，（II）中的两个O-NO₂配体，（III）中的一个氯配体和一个水配体]。分子形状最显著的差异在于这些轴向配体，讨论了它们对分子内和分子间氢键的影响。就（I）而言，所有强氢键供体在分子内相互作用中都已饱和，而弱的分子间C-H∙∙∙O接触形成了三维网络。相反，在（II）和（III）中，存在剩余的N-H和O-H供体用于分子间相互作用，从而形成了强连接但弱相互作用的链。
