Inorganic Chemistry, Vol.35, No.15, 4484-4489, 1996
Synthesis and Characterization of Rhenium(V) Oxo Complexes with a New Thiol-Amide-Thiourea Ligand System - X-Ray Crystal-Structure of (1-Phenyl-3-(2-((2-Thioacetyl)Amino)Ethyl)Thioureato)Oxorhenium(V)
General methods for preparing (ReO)-O-V complexes with a novel series of thiol-amide-thiourea (TATU) Ligands, a new class of N2S2 chelates, were developed. The TATU ligands, the first multidentate systems designed with a bidentate thiourea moiety, have been used to prepare the first high-valent transition metal complexes with bidentate thiourea coordination. Direct reaction of N-(2-aminoethyl)-2-((triphenylmethyl)thio)acetamide (1) with phenyl, 4-methoxyphenyl, 4-chlorophenyl, and methyl isothiocyanate afforded ready access to the corresponding S-protected TATU ligands in one step. A two-step preparation of the N,N-dimethylthiourea TATU ligand derived from 1 was also developed. Deprotection of thiols in trifluoroacetic acid with triethylsilane followed by a ligand exchange reaction with (ReO)-O-V precursors yielded neutral ReO(TATU) complexes.