Cm. Archer et al., TECHNETIUM AND RHENIUM OXO-COMPLEXES OF NEW TETRADENTATE LIGANDS WITHN2S2 AND NS3 DONOR SETS, Journal of the Chemical Society. Dalton transactions, (8), 1997, pp. 1403-1410
A series of new tetradentate, nitrogen-sulfur donor proligands with am
ido or amino donor groups have been synthesized and their rhenium and
technetium ore-complexes prepared. The substitution pattern and length
of the ligand backbone can be varied without affecting the co-ordinat
ion chemistry. The NS3H3 amido-proligands reacted rapidly with the tec
hnetium(V) precursor [TcOCl4](-) at reflux in methanol to give the tec
hnetium(IV) species [TcO(NS3)](-) in very high radiochemical purity (c
a. 100%), but these complexes decompose over a period of hours or days
, They also reacted with the rhenium(V) precursors [ReO2(py)(4)]Cl (py
= pyridine) or [ReOCl3(PPh3)(2)] at reflux in methanol, but only in t
he presence of a base. Stable neutral rhenium(V) complexes of the type
[ReO(NS3)] were formed, and the crystal structures of two determined.
A reduced amino version of the NS3H3 proligand gave an analogous [ReO
(NS3)] complex, and its crystal structure was determined.