Substituent Effects on Formation of Cation Dimers by Weak Hydrogen Bonds in Crystals of Carbonyl Pyridinium Salts of Ni(dmit)<sub>2</sub>
作者:Kazuaki Tomono、Ayako Koyano、Takashi Morita、Kazuo Miyamura
DOI:10.1246/bcsj.82.1152
日期:2009.9.15
Five 1:1 salts of 3-X-1-methylpyridinium (X = benzoyl, acetyl, methoxycarbonyl, carboxy, and aminocarbonyl; abbreviated as Ben, Ace, Met, Car, and Ami, respectively) cations with a [Ni(dmit)2]− anion ([Ben]+[Ni(dmit)2]− (1), [Ace]+[Ni(dmit)2]− (2), [Met]+[Ni(dmit)2]− (3), [Car]+[Ni(dmit)2]− (4), and [Ami]+[Ni(dmit)2]− (5)) have been synthesized and characterized by single-crystal X-ray analysis and conductivity measurements. In the crystals, three cations 1–3 were found to form dimers by weak C–H···O hydrogen bonds, and the arrangements of cations had a strong relation with the electronic effect of the substituents. The cations of 1–3 formed similar centrosymmetrically associated dimers constructed by weak C–H···O hydrogen bonds, whose geometric parameters had a correlation with the electronic effect of the substituents. A cation of 4 also formed centrosymmetrically associated dimer, but it was made by an O–H···O hydrogen bond as usually observed in the case of carboxylic acid. In contrast with other complex salts, cations of 5 formed one-dimensional structure by C–H···O hydrogen bonding. The conductivities of salts 1, 2, 3, 4, and 5 at room temperature were 1.00 × 10−6, 1.10 × 10−6, 2.86 × 10−6, 9.77 × 10−6, and 8.75 × 10−7 S cm−1, respectively.
五种 1:3-X-1-甲基吡啶鎓(X = 苯甲酰基、乙酰基、甲氧羰基、羧基和氨基羰基;缩写分别为 Ben、Ace、Met、Car 和 Ami)阳离子与[Ni(dmit)2]-阴离子([Ben]+[Ni(dmit)2]- (1)、[Ace]+[Ni(dmit)2]- (2)、[Met]+[Ni(dmit)2]- (3)、合成了[Car]+[Ni(dmit)2]- (4) 和 [Ami]+[Ni(dmit)2]- (5)),并通过单晶 X 射线分析和电导率测量进行了表征。在晶体中发现,1-3 三个阳离子通过弱 C-H-O 氢键形成二聚体,阳离子的排列与取代基的电子效应有很大关系。1-3 的阳离子通过弱 C-H-O 氢键形成了类似的中心对称关联二聚体,其几何参数与取代基的电子效应有关。4 的阳离子也形成了中心对称关联的二聚体,但它是通过 O-H-O 氢键形成的,就像通常在羧酸中观察到的那样。与其他复合盐相反,5 的阳离子通过 C-H-O 氢键形成一维结构。盐 1、2、3、4 和 5 在室温下的电导率分别为 1.00 × 10-6、1.10 × 10-6、2.86 × 10-6、9.77 × 10-6 和 8.75 × 10-7 S cm-1。