The hydrogen bond pattern of N-(4-methoxybenzoyl)-N',N"-bis(4-methylbenzyl)-phosphoric triamide, C24H28N3O3P, (I), was investigated. In the crystal structure, the molecules are aggregated through NCP–H•••O═P and NP–H•••O═C hydrogen bonds in a one-dimensional arrangement parallel to the c axis (NCP is the nitrogen atom in the C(O)NHP(O) segment and NP stands for the two other nitrogen atoms bonded to the P atom). There is also a novel NP–H•••π hydrogen bond in the crystal which extends the aggregation of the molecules to a two-dimensional array parallel to the bc plane. A Cambridge Structural Database (CSD, version 5.37, Feb 2016) analysis shows that the N–H•••π hydrogen bond was not observed in any of 156 [RC(O)NH]P(O)[NR1R2]2 (R1≠H, R2= H or≠H) phosphoric triamide structures reported so far. The theoretical calculations at the B3LYP/6-311G∗∗ level of theory (DFT, AIM, and NBO) were performed to evaluate the strengths of NCP–H•••O═P, NP–H•••O═C and NP–H•••π hydrogen bonds, considering two-aggregate molecular assemblies containing these hydrogen bonds. The calculations on the title compound suggest that the intermolecular NCP–H•••O═P hydrogen bond is stronger than NP–H•••O═C and NP–H•••π interactions. The hydrogen bond strength was investigated by NBO, topological analysis, geometry calculation, Hirshfeld surface analysis and experimental spectroscopic results, which are in agreement with each other.

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