Phosphinamides, with a C2P(O)N fragment, are well-known for flame-retardancy properties [1]. In this work, the synthesis, spectroscopy, thermogravimetry and X-ray crystallography of N, N\\\\\\\\\\\\\\\'-(cyclohexane-1,4-diyl)-bis(P, P-diphenylphosphinic amide) are studied. The compound crystallizes in the monoclinic space group C2/c. The asymmetric unit is composed of one half of the molecule, and the complete molecule is generated by an inversion element. The P atom has a distorted tetrahedral C2P(O)N enviroment, and the maximum and minimum bond angles at phosphorus are related to N—P═O (120.23 (6)°) and N—P—C (101.95 (7)°). The bond-angle sum at nitrogen (about 353°) confirms its sp2 character. The P═O bond length (1.4864 (11) Å) is slightly longer than the typical phosphorus-oxygen double bond length and is comparable to those in analogous compounds [2, 3]. The P—N bond length (1.6407 (13)Å) is standard for structures with a C2P(O)N skeleton [3]. The NH unit adopts a synclinal orientation with respect to the P═O group. In the crystal structure, the molecules are aggregated through N—H…O hydrogen bond in a two dimensional assembly along the bc plane. The 31P NMR spectrum shows one signal at 19.91 ppm indicating the high purity of the compound. In the IR spectrum, the band centered at 3133 cm–1 corresponds to the N—H stretching. The TGA exhibits the starting decomposition point at about 250 °C

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