Lipophilic technetium complexes. V. Synthesis and characterization of (3-thiapentane-1,5-dithiolato)(thiophenolato)oxotechnetium(V)

Synthesis and characterization of complexes of the {ReO}3+ core with SNS and S donor ligands

“…All display a series of multiplets ranging from 6.84 to 8.72 ppm assignable to the eight aromatic protons, as well as four multiplets at 2.69, 2.87, 3.53, and 3.85 ppm assignable to each CH 2 moiety comprising the backbone of the tridentate ligand ( − SCH 2 CH 2 N(R)CH 2 CH 2 S − ). All four of the multiplets integrate to two protons; however, individual assignments of the resonances are tenuous at best, due to the multiplicity of the peaks and the flexibility of the ligand in solution, as noted by others [6]. In addition, compounds 2-6 also displayed a single proton resonance integrating to two protons at 5.03 ppm corresponding to the methylene spacer of the tridentate backbone.…”

“…The synthesis of novel compounds, which allow the systematic exploration of size, shape, molecular weight, and charge of the metal-thiolate complexes with respect to their biodistribution patterns, provides a driving force for advances in the radiopharmaceutical chemistry of rhenium. One approach to the systematic design of Re(V) complexes with the {ReO} 3+ core exploits the '3+1' concept of ligand addition to a Group 7 metal-oxo species [6][7][8][9][10][11][12][13][14][15][16]. The methodology is based on forming a tridentate '3' and a monodentate '1' mixedthiolate core.…”

Schiff base chemistry of the {ReO}3+ core: structural characterization of the unusual ‘3+2’ complex [ReO(η3-OC6H4–CHNC6H4-2-S)(η2-OC6H4)]

“…One approach to the design of novel reagents has focused on polydentate ligands with thiolate and nitrogen donors with the robust {ReO} 3+ core [6]. The '3+1' concept of ligand addition provides a strategy for the consistent synthesis of {ReO} 3+ core complexes, allowing a systematic investigation of the size, shape, molecular weight, and charge of the rheniumthiolate complexes [7][8][9][10]. The concept is based on ligation of a dinegative tridentate unit with the ( − S-X-Y − ) donor set (X = O, S, NR; Y = S, O) in combination with a mononegative thiol, so as to preserve the oxometal core and the formal +5 oxidation state of the metal.…”

Investigations of the {ReO}3+ core: A ‘2+2’ complex from bidentate and potentially trident ligands: [ReO(η2-HOC6H4-2-CH2NC6H4S)(η2-SC5H4N)(PPh3)]

“…In this connection, one approach has focused on the robust {ReO} 3+ core in combination with ligands possessing different donor sets and denticities. The most extensively developed strategy exploits '3+1' ligand combinations, which contain a dianionic tridentate ligand with various donor atoms, but requiring at least one thiolate sulfur, and a monodentate thiol [6][7][8][9]. In addition, '2+2' ligand combinations [10] and more recently '3+2' chelates have been exploited [11,12].…”