Organophosphorus ligands with XPNSO skeleton (X=O, S) and their Pd(II) complexes. Crystal and molecular structure of [{XP(OEt)2}(O2SR)]NH (X=O, R=Me, Ph; X=S, R=C6H4Cl-4) and Pd[{SP(OEt)2}(O2SC6H4Cl-4)N]2

Two new thiophosphoramide structures: N,N',N''-tricyclohexylphosphorothioic triamide and O,O'-diethyl (2-phenylhydrazin-1-yl)thiophosphonate

The compound N,N',N''-tricyclohexylphosphorothioic triamide, C18H36N3PS or P(S)[NHC6H11]3, (I), crystallizes in the space group Pnma with the molecule lying across a mirror plane; one N atom lies on the mirror plane, whereas the bond-angle sum at the other N atom has a deviation of some 8° from the ideal value of 360° for a planar configuration. The orientation of the atoms attached to this nonplanar N atom corresponds to an anti orientation of the corresponding lone electron pair (LEP) with respect to the P=S group. The P=S bond length of 1.9785 (6) Å is within the expected range for compounds with a P(S)[N]3 skeleton; however, it is in the region of the longest bond lengths found for analogous structures. This may be due to the involvement of the P=S group in N-H···S=P hydrogen bonds. In O,O'-diethyl (2-phenylhydrazin-1-yl)thiophosphonate, C10H17N2O2PS or P(S)[OC2H5]2[NHNHC6H5], (II), the bond-angle sum at the N atom attached to the phenyl ring is 345.1°, whereas, for the N atom bonded to the P atom, a practically planar environment is observed, with a bond-angle sum of 359.1°. A Cambridge Structural Database [CSD; Allen (2002). Acta Cryst. B58, 380-388] analysis shows a shift of the maximum population of P=S bond lengths in compounds with a P(S)[O]2[N] skeleton to the shorter bond lengths relative to compounds with a P(S)[N]3 skeleton. The influence of this difference on the collective tendencies of N···S distances in N-H···S hydrogen bonds for structures with P(S)[N]3 and P(S)[O]2[N] segments were studied through a CSD analysis.