Anzaldo-Olivares Bertin, Arroyo Maribel, Ramírez-Monroy Armando, Bernès Sylvain
Centro de Química del Instituto de Ciencias, Benemérita Universidad Autónoma de Puebla, Ciudad Universitaria, 72570 Puebla, Pue., Mexico.
Instituto de Física, Benemérita Universidad Autónoma de Puebla, Av. San Claudio y 18 Sur, 72570 Puebla, Pue., Mexico.
IUCrdata. 2020 Mar 5;5(Pt 3):x200281. doi: 10.1107/S2414314620002813. eCollection 2020 Mar.
The structure of the tertiary amine tris-(1-benzimidazol-2-ylmeth-yl)amine (CHN, abbreviated ntb) has been previously reported twice as solvates, namely the monohydrate and the aceto-nitrile-methanol-water (1/0.5/1.5) solvate, both with the tripodal conformation formed multiple hydrogen bonds. Now, we report the tri-methanol adduct, ntb·3CHOH, where the amine has the stair conformation featuring one benzimidazole group oriented in the opposite direction from the other two. The asymmetric unit contains one-half amine, completed through the mirror plane in space group 2 to form the ntb mol-ecule, with the H atom for each imidazole moiety equally disordered between both N sites available in the imidazole ring. The asymmetric unit also contains one and a half methanol mol-ecules, one being placed in general position with the hy-droxy H atom disordered over two sites with occupancy ratio 1:1, while the other lies on the mirror plane, and has thus its hy-droxy H atom disordered by symmetry. As in the previously reported solvates, all imine and amine groups of the ntb mol-ecules and the methanol mol-ecules are involved in N-H⋯O and O-H⋯N hydrogen bonds. In the title compound, however, the involved H atom is systematically a disordered H atom provided by an imidazole group or a methanol mol-ecule.
叔胺三(1 - 苯并咪唑 - 2 - 基亚甲基)胺(CHN,缩写为ntb)的结构先前曾两次报道为溶剂化物,即一水合物和乙腈 - 甲醇 - 水(1/0.5/1.5)溶剂化物,二者均具有三脚架构象并形成多个氢键。现在,我们报道其三甲醇加合物ntb·3CH₃OH,其中胺具有阶梯构象,其一个苯并咪唑基团的取向与另外两个相反。不对称单元包含半个胺,通过空间群2中的镜面完成以形成ntb分子,每个咪唑部分的H原子在咪唑环中两个可用的N位点之间同等无序。不对称单元还包含一个半甲醇分子,一个处于一般位置,其羟基H原子在两个位点上无序排列,占有率为1:1,而另一个位于镜面上,因此其羟基H原子通过对称而无序。与先前报道的溶剂化物一样,ntb分子和甲醇分子的所有亚胺和胺基团都参与N - H⋯O和O - H⋯N氢键。然而,在标题化合物中,所涉及的H原子系统地是由咪唑基团或甲醇分子提供的无序H原子。