Tris(1H-benzimidazol-2-ylmeth-yl)amine methanol tris-olvate.

Bertin Anzaldo-Olivares,Armando Ramírez-Monroy,Maribel Arroyo,Sylvain Bernès

doi:10.1107/s2414314620002813

Abstract

The structure of the tertiary amine tris-(1H-benzimidazol-2-ylmeth-yl)amine (C24H21N7, 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 via multiple hydrogen bonds. Now, we report the tri-methanol adduct, ntb·3CH3OH, 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 m in space group Pmn21 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 m 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.

Highlights

The structure of the tertiary amine tris(1H-benzimidazol-2-ylmethyl)amine (C24H21N7, abbreviated ntb) has been previously reported twice as solvates, namely the monohydrate and the acetonitrile–methanol–water (1/0.5/1.5) solvate, both with the tripodal conformation formed via multiple hydrogen bonds
The asymmetric unit contains one and a half methanol molecules, one being placed in general position with the hydroxy H atom disordered over two sites with occupancy ratio 1:1, while the other lies on the m mirror plane, and has its hydroxy H atom disordered by symmetry
As in the previously reported solvates, all imine and amine groups of the ntb molecules and the methanol molecules are involved in N—HÁ Á ÁO and O—HÁ Á ÁN hydrogen bonds

Summary

DÁ Á ÁA

C7. . .N4 of 1.338 (4) and 1.335 (4) A. Given that all imidazolic H atoms are disordered, the same holds for hydroxy H atoms: the first methanol molecule C14—O1 lies in the mirror m plane, with its H atom disordered by symmetry (H1); the second methanol molecule, C15—O2, placed in general position, has its hydroxy H atom disordered over two sites, H2A and H2B, with half occupancy (Fig. 2). With this arrangement, any physically unreasonable HÁ Á ÁH contact is avoided, despite all heteroatoms, except N1, being involved in efficient hydrogen bonds. C24H21N7Á3CH4O 503.60 Orthorhombic, Pmn21 293 16.7781 (17), 16.3902 (18), 4.7894 (5) 1317.1 (2) 2 Mo K 0.09 0.77 Â 0.17 Â 0.10

Data collection Diffractometer Absorption correction

Synthesis and crystallization

Crystal data

Data collection

Special details