Synthesis of 5-(arylmethylideneamino)-4-(1H-benzo[d]imidazol-1-yl)pyrimidine hybrids: synthetic sequence and the molecular and supramolecular structures of two intermediates and three final products

A concise and versatile synthesis of 5-(arylmethylideneamino)-4-(1H-benzo[d]imidazol-1-yl)pyrimidines has been developed, starting from 4-(1H-benzo[d]imidazol-1-yl)pyrimidines, and we report here the synthesis and spectroscopic and structural characterization of three such products, along with those of two intermediates in the reaction pathway. The intermediates 4-[2-(4-chlorophenyl)-1H-benzo[d]imidazol-1-yl]-6-methoxypyrimidine-2,5-diamine, (II), and 4-[2-(4-bromophenyl)-1H-benzo[d]imidazol-1-yl]-6-methoxypyrimidine-2,5-diamine, (III), crystallize as the isostructural monohydrates C18H15ClN5O · H2O and C18H15BrN5O · H2O, respectively, in which the components are linked into complex sheets by O — H...N and N — H...O hydrogen bonds. In the product (E)-4-methoxy-5-[(4-nitrobenzylidene)amino]-6-[2-(4-nitrophenyl)-1H-benzo[d]imidazol-1-yl]pyrimidin-2-amine, which crystallizes as a 1:1 solvate with dimethyl sulfoxide, C25H18N8O5 · C2H6OS, (IV), inversion-related pairs of the pyrimidine component are linked by N — H...N hydrogen bonds to form cyclic centrosymmetric R22(8) dimers to which pairs of solvent molecules are linked by N — H...O hydrogen bonds. (E)-4-Methoxy-5-[(4-methylbenzylidene)amino]-6-[2-(4-methylphenyl)-1H-benzo[d]imidazol-1-yl]pyrimidin-2-amine, C27H24N6O, (V), crystallizes with Z ′   = 2 and the molecules are linked into a three-dimensional framework structure by a combination of N — H...N, C — H...N and C — H... π (arene) hydrogen bonds. The ...

Source: Acta Crystallographica Section C - May 4, 2023 Category: Chemistry Authors: Vicentes, D.E. Rodr í guez, R. Cobo, J. Glidewell, C. Tags: synthesis pyrimidine heterocyclic hybrid NMR spectroscopy crystal structure molecular structure molecular conformation hydrogen bonding supramolecular assembly research papers Source Type: research