Thiophosphinic amide complexes of rhenium

Upon the reaction of thiophosphinic acid amides (C6H5)PNH2S (1a) or (CH3)2PNH2S (1b) with [BrRe(CO)4]2 (2a), according to Eq. (I), the monomeric substitution products R2PNH2SRe(CO)4Br (R = C6H5 (3a), CH3 (3b)) are obtained with a single P-S-Re linkage. Compounds 3a and 3b release CO upon heating in C6H6 according to Eq. (2), leading to the formation of the presumably polymeric tricarbonylrhenium complexes R2PNH2SRe(CO)3Br (R = C6H5 (4a), CH3 (4b)). In 4a and 4b, 1a and 1b are bidentate coordinated to rhenium through nitrogen and sulfur. Compounds 4a and 4b are also formed from 1a and 1b and BrRe(CO)5 (2b). The newly synthesized complexes 3a, 3b, and 4a, 4b are characterized by IR, Raman, and 1H-NMR spectroscopy.