Extension of the Karplus relationship to vicinal coupling within the P-Ru-S-H moiety of the H2S complexes cis-RuX2(P-N)(PPh3)(SH2) X = Cl, Br; P-N = [o-(N,N-dimethylamino)phenyl]diphenylphosphine

The Ru(II)-H2S complexes cis-RuX2(P-N)(PPh3)(SH2) {X = Cl, Br; P-N = [o-(N,N-dimethylamino)phenyl]diphenylphosphine} are characterised crystallographically and by P-31{H-1}, H-1 and H-1{P-31} NMR spectroscopies; the H-1 NMR spectra at -50 degrees C show three-bond coupling of only one H-atom of the coordinated H2S to the P-atom of the P-N ligand, and this represents an extension of the Karplus relationship to vicinal coupling within a P-Ru-S-H system.