Technetium Chlorides and Oxochlorides

Abstract

We have been unable t o prepare TcCI, by the method published previously even though our reaction between Tc and CI, gave products which appeared the same. Tc0,CI and TcOCI, have been prepared and fully characterized for the first time.11 a ete impossible de preparer TcCI, par la methode precedemment publiee, m@me si la reaction entre Tc et CI, conduit a des produits qui semblent les m&mes. Les composes Tc0,CI et TcOCI, ont ete prepares et caracterises sans ambigui'tt pour la premiire fois.

The Present Status of Technetium Chemistry

“…Technetium burns in oxygen at 500°C to Tc 2 0 7 [47], in fluorine to a mixture of the penta-and hexafluorides [48]. It reacts with chlorine at 550°C to TcCl 4 ; TcOCl 4 and Tc0 3 Cl are formed precedingly if the chlorine contains some oxygen [49]. Sulfur combines at elevated temperatures to give the disulfide [48].…”

“…The metastable form of TcOF 4 is a green volatile solid, the structure of which is based on trimeric units [48]. TcCl 4 was synthesized by reaction of technetium metal powder with chlorine at 300-550°C, in the course of which purple TcOCl 4 and pale yellow Tc0 3 Cl are also formed [49]. Technetium tetrachloride can also be prepared by the interaction of Tc 2 0 7 with CC1 4 at 400 °C [97], The dark red needles of TcCl 4 crystallize orthorhombically in the space group Pbca; distorted octahedral TcCl 6 units are linked to form polymeric chains [98].…”

Permanganyl Fluoride: A Brief History of the Molecule MnO3F and of Those Who Cared For It

“…The preparation of pertechnetyl chloride TcO 3 Cl (in several papers also named pertechnyl chloride) has been achieved via several routes including the reaction of technetium chlorides with oxygen and of technetium metal with chlorine and a non‐specified origin for oxygen. The product was described as a volatile yellow liquid [46, 47] . In several reports the vibrational and the vapor phase UV/Vis absorption spectra have been described and assigned in comparison with those of the rhenium analogue.…”

New Organometallic Technetium Complexes in High and Low Oxidation States

“…Organometallic Tc(VII) complexes were previously not known and so we focused our attention on CH3TCO3 2, its properties, and when present, its catalytic reactivity. Only a very few Tc(VII) Compounds containing the "TcOa " are known ( Figure 1) and with the exception of 3 all were prepared within the last three years [4,5,6,7], Synthesis of 5 and 6 goes along with the Re analog. We investigated the different behaviour of rhenium and technetium following example of CH3TCO3 with respect to oxidation catalysis and found the differences are not only gradual but fundamental.…”