Ronald M. Pearlstein

Technetium-99 NMR spectroscopy: chemical shift trends and long range coupling effects

Abstract Values for the chemical shifts and linewidths of a variety of technetium compounds in oxidation states V, III and I were measured. Correlations between the shift and oxidation state, ligand field strength and shielding effects for these, and other previously measured compounds, are discussed. An extensive series of substituted hexakis(isonitrile)technetium(I) compounds was studied which exhibits a chemical shift range of over 75 ppm. Studies of coupling between 99 Tc and other nuclei, including four-bond, long range 99 Tc- 1 H coupling, are described.

Alkene-glycol interconversion with technetium and rhenium oxo complexes

Abstract The trioxotechnetium(VII) complexes TcO 3 Cl(AA) (AA = phen, bpy, 5-NO 2 -phen, 3,4,7,8-Me 4 -phen) cleanly oxidize olefins (C 2 R 4 ) in solution at 22°C, forming in high yields the corresponding oxotechnetium(V) diolate complexes, TcOCl(OCR 2 CR 2 O)(AA). The complexes have been characterized by 1 H NMR, IR, elemental analysis, and fast atom bombardment mass spectrometry. The free diols isolated by hydrolysis of these diolate complexes with HCl were shown by capillary gas chromatography to represent syn addition of the two hydroxyl groups across the double bond. The related rhenium complex, ReOCl(OCH 2 CH 2 O)(phen) undergoes the reverse reaction when thermalized, releasing ethylene and producing ReO 3 Cl(phen).