A novel halogen-bridged system: synthesis and structures of dibromo[2-(2-aminomethyl)pyridine]copper(II) and dibromo(2-methyl-1,2-diaminopropane)copper(II)
A novel halogen-bridged system: synthesis and structures of dibromo[2-(2-aminomethyl)pyridine]copper(II) and dibromo(2-methyl-1,2-diaminopropane)copper(II)
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一种新型卤桥体系：二溴[2-(2-氨基甲基)吡啶]铜(II)和二溴(2-甲基-1,2-二氨基丙烷)铜(II)的合成和结构
DOI：
10.1021/ic50175a050
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发表时间：
1977
影响因子：
4.6
通讯作者：
D. Hodgson
中科院分区：
文献类型：
--
作者：
H. M. Helis;W. H. Goodman;R. B. Wilson;J. A. Morgan;D. Hodgson
合成了二溴[2-(2-氨基甲基)吡啶]铜(II)配合物CuC6H8N2Br2，并测定了该配合物与二溴(2-甲基-L，2-二氨基丙烷)铜(II)的晶体结构。氨甲基吡啶配合物属单斜晶系，空间群为P2/m，晶胞尺寸为a=8.222(15)，b=6.372(13)，c=9.883(18)？，？=116.3(1)，测得密度和计算密度分别为2.51g cm™3和2.43g cm P3。该结构已通过全矩阵最小二乘法进行了改进，以763个独立观测值为基础，将传统的R因子(在P上)的最终值定为0.046。二氨基丙烷配合物结晶为正交晶系Pnma空间群，晶胞尺寸为a=20.276(28)，b=6.208(3)，c=7.058(3)，有四个分子式单位，测得密度和计算密度分别为2.33g cm™3和2.330 g cmPn3。根据669个强度，该结构已被优化为最终的R值0.039。在这两种络合物中，公式单元都被限制在晶体镜面中，这在两种情况下都是ac平面。对于2-甲基-1，2-二氨基丙烷络合物，这会导致四个碳原子中的三个无序。这两种结构都由无限的二溴桥链组成，其中一个溴配体用于向两个方向传播链，而另一个不参与链；因此，一个溴与三个铜原子配位，而另一个只与一个铜原子配位。这种形式的链条是独一无二的。每个铜中心的几何形状是扭曲的八面体，平面内有两个顺式氮原子和两个溴原子，平面外有较弱的链传播溴化物相互作用。氨甲基吡啶和二氨基丙烷的铜-铜分离度分别为3.737(6)和3.866(2)，相应的铜-溴-铜桥联角分别为80.77(4)和87.56(3)。
The complex dibromo [2-(2-aminomethyl) pyridine] copper (II), CuC6H8N2Br2, has been synthesized, and the crystal structures of this complexand of dibromo (2-methyl-l, 2-diaminopropane) copper (II), CuC4H12N2Br2, have been determined. The aminomethylpyridine complex crystallizes in the monoclinic space group P2,/m, withtwo formula units in a cell of dimensions a= 8.222 (15), b= 6.372 (13), c= 9.883 (18) Á, and ß= 116.3 (1), with observed and calculated densities of 2.51 and 2.43 g cm™ 3, respectively. The structure has been refined by full-matrix least-squares methods to a final value of the conventional R factor (on P) of 0.046 based on 763 independent observations. The diaminopropane complex crystallizes in the orthorhombic space group Pnma, with four formula unitsin a cell of dimensions a= 20.276 (28), b= 6.208 (3), and c= 7.058 (3) Á and observed and calculated densities of 2.33 and 2.330 g cm™ 3, respectively. The structure has been refined to a final value of R of 0.039 based on 669 intensities. In bothcomplexes, the formula unit is constrained to lie in a crystallographic mirror plane, which is the ac plane in both cases. For the 2-methyl-1, 2-diaminopropane complex, this brings about a disorder of three of the four carbon atoms. Both structures consist of infinite dibromo-bridged chains, in which one bromide ligand serves to propagate the chain in both directionswhile the other is not involved in the chain; thus, one bromide is coordinated to three copper atoms while the other is coordinated to only one. This form of chain is unique. The geometry about each copper center is distorted octahedral, with two cis nitrogen atoms and two bromidesin the plane and the weaker chain-propagating bromide interactions out of the plane. The Cu-Cu separations in the two chains are 3.737 (6) and 3.866 (2) Á for the aminomethylpyridine and diaminopropane complexes, respectively, with associated Cu-Br-Cu bridging angles of 80.77 (4) and 87.56 (3), respectively.