Technetium complexes of 3,5-di-tert-butylcatechol. Direct synthesis of tris(3,5-di-tert-butylcatecholato)technetium(VI) and bis(3,5-di-tert-butylcatecholato)-(di-tert-butylamidophenolato)technetium(VI) from ammonium pertechnetate

Journal Article · Wed Jun 07 04:00:00 EDT 1989 · Journal of the American Chemical Society; (USA)

DOI:https://doi.org/10.1021/ja00194a025· OSTI ID:7059748

deLearie, L A; Haltiwanger, R C; Pierpont, C G ^[1]

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1. Univ. of Colorado, Boulder (USA)

The reaction between 3,5-di-tert-butylcatechol and ammonium pertechnetate in methanol produces a mixture of tris(3,5-di-tert-butylcatecholato)technetium(VI) (Tc(DBCat){sub 3}) and bis(3,5-di-tert-butylcatecholato)(di-tert-butylamido-phenolato)technetium(VI) (Tc(DBCat){sub 2}(DBAP)). The amidophenolate ligand of Tc(DBCat){sub 2}(DBAP) appears to result from Schiff-base condensation of ammonia from ammonium ion with catechol. When the reaction is carried out in the present of excess, 3,5-di-tert-butylcatechol only small quantities of Tc(DBCat){sub 2}(DBAP) are formed. Crystallographic characterization of Tc(DBCat){sub 3} has shown that the molecule crystallizes in the monoclinic space group P2{sub 1}/n in a unit cell of dimensions a = 15.892 (3) {angstrom}, b = 15.878 (4) {angstrom}, c = 16.367 (3) {angstrom}, {beta} = 93.13 (1){degree}, and V = 4123 (1) {angstrom}{sup 3}. The complex molecule is of C{sub 3} symmetry and the average ligand C-O bond length of 1.334 (13) {angstrom} is typical of values found for catecholate ligands. As such, the complex is a unique example of Tc(VI). Both Tc(DBCat){sub 3} and Tc(DBCat){sub 2}(DBAP) exhibit well-resolved 10-line EPR spectra in solution at room temperature. Coupling to the {sup 99}Tc nucleus (I = 9/2) of approximately 140 G is consistent with the d{sup 1} Tc(VI) formulation for both complexes. They each undergo reversible one-electron oxidations to cationic complexes with surprising ease, and they each undergo two reversible one-electron reductions to Tc(V) and Tc(IV) forms of the complexes.

• OSTI ID: 7059748
• Journal Information: Journal of the American Chemical Society; (USA), Journal Name: Journal of the American Chemical Society; (USA) Vol. 111:12; ISSN 0002-7863; ISSN JACSA
• Country of Publication: United States
• Language: English

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63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
COMPLEXES
COORDINATION NUMBER
DATA
DATA ANALYSIS
DRUGS
EXPERIMENTAL DATA
INFORMATION
LABELLED COMPOUNDS
MEASURING INSTRUMENTS
MEASURING METHODS
MEDICINE
NUCLEAR MEDICINE
NUMERICAL DATA
RADIOPHARMACEUTICALS
SYNTHESIS
TECHNETIUM COMPLEXES
TRANSITION ELEMENT COMPLEXES