Preparation of oxobis(dithiolato) complexes of technetium(V) and rhenium(V)

Structure of a neutral N-alkylated diaminedithiol (dadt) 99TcV complex: syn[99TcO(NEt-tmdadt)]

“…The Tc--S bond lengths are similar to those observed for a number of Tc-thiolate complexes (Davison et al, 1980;DePamphilis, Jones, Davis & Davison, 1978). However, there is a notable difference between the two Tc--S bonds.…”

The preparation, characterization, and crystal and molecular structure of oxobis(ethan-1,2-dithiolato-S,µS′)technetium(V)oxo(ethan- 1,2-dithiolato-S,S′)technetium(V) [(TcO)2(SCH2CH2S)3]. A Tc(V) compound containing metal—sulfur—metal bridges

“…All manipulations were carried out following precautions which have been detailed elsewhere (9). All reagents were used as received unless otherwise specified.…”

“…In order to test its effectiveness as a protecting group for thiols in the NzS2 system, bis(acetamidomethyl)ethanedithiol (edt(a~m)~) was prepared as a model and studied in its reactions with TcO,-and [TcOCI,]-. The desired product was the well-characterized (8,9) [T~O(edt)~]-ion, but, in addition, an apparent intermediate [(T~O)~(edt),] was isolated in the study. The same intermediate was isolated during ligand-exchange studies of oxotechnetium(V) complexes (10).…”

Final Report, Research Program to Investigate the Fundamental Chemistry of Technetium

“…Except for thiolate complexes (Davison 1980), all known reduced technetium complexes, which are stable to hydrolysis in alkaline aqueous solution, are air sensitive.…”

“…Few technetium complexes are known to be stable in basic solution. Dithiolate ( -SCH 2 CH 2 S -) complexes of Tc(V) are extremely stable in aqueous solution including alkaline solutions (Davison 1980 (Davison 1987) and Tc(IV) (Alberto 1986) are stable only in alkaline aqueous solution; they decompose to TcO 2 •xH 2 O at pH < 10.…”