名称:
Crystal Structure and NQR Studies of Compounds (RH)[ZnBr3(R)], (RH)2[ZnBr4] and [ZnBr2(R)2] (R = Py, n-MePy: n = 2, 3, 4); on the Dominant Stability of the Monoanionic Complexes over the Dianionic and Neutral Species
摘要:
通过从乙醇溶液中晶化,通过相应的二阴离子配合物(C5H5NH)2[ZnBr4](5)和(n-CH3C5H4NH)2[ZnBr4](n = 2,3(6),4(7))与中性配合物[ZnBr2(C5H5N)2](10)和[ZnBr2(n-CH3C5H4N)2](n = 2(8),3,4(9))之间的重新分配反应制备了单阴离子配合物(C5H5NH)[ZnBr3(C5H5N)](1)和(n-CH3C5H4NH)[ZnBr3(n-CH3C5H4N)](n = 2(2),3(3),4(4))。确定了1、4、9和10的晶体结构;1:三斜晶系,P1,a = 7.6957(5),b = 7.7975(4),c = 12.4768(8)Å,α = 90.857(5),β = 95.917(5),γ = 107.899(6)°,Z = 2,150 K;4:单斜晶系,P21/c,a = 14.8369(6),b = 13.9504(5),c = 8.0041(3)Å,β = 96.318(4)°,Z = 4,299 K;9:单斜晶系,P21/c,a = 14.2883(5),b = 8.0269(3),c = 13.6031(5)Å,β = 100.581(4)°,Z = 4,150 K;10:单斜晶系,P21/c,a = 8.7388(5),b = 17.9730(10),c = 8.5452(5)Å,β = 100.024(6)°,Z = 4,300 K。在1-5和7-9化合物中,从77到约320 K的温度范围内观察到与化学式中的Br原子数量相符的81Br NQR共振线。通过Townes-Daily分析或Mulliken电荷分析得到的Br原子的净电荷之间的比较似乎表明,晶体结构中的分子间N-H···Br氢键、π-π和CH3-π相互作用是单阴离子配合物的重新分配反应的驱动力。在1的结构中,阳离子和阴离子通过分叉氢键成对出现,在4的结构中,它们通过正常的N-H···Br氢键成对出现。