Competing and directing interactions in new phosphoramide/thiophosphoramide structures: energy considerations and evidence for CH HC contacts and aliphatic-aromatic stacking

• Published in: CrystEngComm 2023-04, Vol.25 (17), p.2557-2569
• Main Authors: Hosseinpoor, Saeed, Pourayoubi, Mehrdad, Abrishami, Mozhgan, Sobati, Marjan, Karimi Ahmadabad, Fatemeh, Sabbaghi, Fahimeh, Ne as, Marek, Dušek, Michal, Ku eráková, Monika, Kaur, Manpreet
• Format: Article
• Language: English
• Subjects: Bonding strength; Chemical bonds; Crystallography; Hydrogen bonds; Lattice energy; Stacking; Structural members
• ISSN: 1466-8033; 1466-8033
• DOI: 10.1039/d3ce00204g

Supramolecular aggregates, driven by different molecular functionalities and crystal forces, are studied in new phosphoramide and thiophosphoramide structures (C 6 H 5 O) 2 P(O)(2-NHC 5 H 4 N) ( I ), (4-Cl-C 6 H 4 O)P(O)(NHC 6 H 11 ) 2 ( II ), (4-Cl-C 6 H 4 O)P(O)(N(CH 3 )C 6 H 11 ) 2 ( III ), P(S)(NHC(CH 3 ) 3 ) 3 ( IV ), and P(S)(3-NHC 5 H 4 N) 3 ( V ). DH A (D = N, C; A = N, O, S) hydrogen bonds, contacts related to the ring stacking (CH π/σ π and π π) and some other weak interactions are the structural elements inspected. The techniques/methods used are X-ray crystallography, QTAIM, NCI, 2D fingerprint plots, and lattice energy calculations, complemented by spectroscopic approaches for some additional investigations. A comparison is made with selected analogous structures from the Cambridge Structural Database (CSD). Determinative roles of stronger hydrogen bonds and competition between weaker hydrogen bonds (mostly having dispersion characteristics) are addressed as well as the cyclohexyl arene (σ π) stacking with pronounced CH π interactions. When the strength and specificity of the hydrogen bonds decrease, the molecules can form a denser packing, and the role of CH HC interactions becomes prominent. Despite their weakness, such interactions together make the bulk of the crystal stabilizing forces. Structural analysis of a set of phosphoramide/thiophosphoramide derivatives by scrutinizing the energy and topological calculations discloses the role of individual interactions in crystal formation.