Synthesis, Spectroscopic Study, X-Ray Crystallography Investigation and Hirshfeld Surface Analysis of Three New Phosphorous-Nitrogen Compounds

Abstract

New phosphorous-nitrogen compounds 2,3-F2—C6H3C(O)NHP(O)[N(CH3)CH2C6H5]2 (I), C6H5OP(O)[NHCH(CH3)2]2 (II) and (CH3O)2P(S)[NHC6H4NH]P(S)(OCH3)2 (III) were synthesized and characterized by 19F NMR for (I) and 1H, 13C, 31P NMR and IR and mass spectroscopy and single crystal X-ray determination for all three compounds. In the 31P NMR spectra, the 31P{1H} signals of (I), (II) and (III) are revealed at 12.95, 10.49 and 69.55 ppm, respectively. The chemical shits observed are within the expected values for analogous phsophoramide and thiophosphoramide compounds.1,2 In the crystal structure of (I), centrosymmetric dimers are built from pairs of N—H…O═P hydrogen bonds. In the structure (II), the molecules are aggregated in a one-dimensional arrangement via N—H…O═P hydrogen bonds along the b axis. In the structure (III), the two-dimensional array is generated from the N—H…O hydrogen bonds along the ab plane. In structure (II), the oxygen atom of P═O group is a better H-atom acceptor than the oxygen atom of the C6H5O group, as the latter oxygen atom doesn’t take part in hydrogen bonding interaction. The better hydrogen-bond acceptor capability of P═O group with respect to the oxygen atom of RO group in structures with an [RO]P(O)[N]2 segment were analyzed through the analysis of the structures deposited in the Cambridge Structural Database. In contrast with the structure (II), in the structure (III), the O atom of CH3O group is involved in N—H….O hydrogen bonding, whereas, the P═S group doesn’t take part in the hydrogen bonding interaction (Fig. 1). The Hirshfeld surfaces and fingerprint plots3 were also employed for analysis of intermolecular interactions.<br><br>Fig. 1. A crystal packing diagram for structure (III) is represented, showing a 2D network that formed by N-H…O hydrogen bonds.<br><br>References<br><br>1 M. Pourayoubi, M. Abrishami, V. Eigner, M. Nečas, M. Dušek, M. Delavar, Acta Cryst., 2014, C70, 1147–1152.<br><br>2 M. Toghraee, M. Pourayoubi, V. Divjakovic, Polyhedron, 2011, 30, 1680–1690.<br><br>3 M. A. Spackman, J. J. McKinnon, CrystEngComm, 2002, 4, 378–392.