Intramolecular hydrogen bond controlled monodentate S-coordination of N-phosphoryl-N′-(R)-thioureas with Pd(II)

Reaction of N-phosphorylated thioureas RNHC(S)NHP(O)(OiPr)2 (R = tBu, HLI; R = Ph, HLII; R = 4′-benzo-15-crown-5, HLIII) with Pd(PhCN)2Cl2 in acetonitrile leads to complexes of formulae Pd(HLI-S)2Cl2 (1), Pd(HLII-S)2Cl2 (2) and Pd(HLIII-S)2Cl2 (3). The crystal structure of complex 1 has been investigated by X-ray crystallography. It was established that the thiourea ligands are in a trans-configuration and the palladium(II) cation is coordinated by the sulfur atoms of the Cdouble bond; length as m-dashS groups and the chlorine atoms. Complex 1 is the first example of palladium(II) complex in which the potentially chelating N-phosphorylated thiourea ligand is bound through the sulfur atom only.