Technetium radiopharmaceutical development. 1. Synthesis, characterization, and structure of dichloro[hydrotris(1-pyrazolyl)borato]oxotechnetium(V)

Abstract

Der neutrale lipophile Titelkomplex (I) wird durch Reduktion von Ammoniumpertechnetat (99Tc) mit K‐tetrahydridoborat in wäßriger 3 M HCl‐Lösung in Gegenwart von K‐hydrido‐tris‐[ l‐pyrazolyl]‐borat dargestellt und durch IR‐, Raman‐ sowie NMR‐Spektren charakterisiert.

Substituent Effect on the Structure and Biological Property of99mTc-Labeled Diphosphonates: Theoretical Studies

“…The basal plane is defined by four oxygen atoms (O4, O6, O12 and O18) of the DP and hydroxyl ligands, and the apical positions are occupied by another two oxygen atoms (O14 and O19) of the DP and hydroxyl ligands. Inspecting the optimized structure of the prototypical complex 99m Tc-MDP, the calculated Tc-O bond lengths are found to vary from 2.007 to 2.088 Å, which are generally in line with the observed Tc-O single bond lengths (2.00-2.03 Å) 30 since Tc=O double bond lengths are considerably shorter (1.65-1.70 Å). 30 Compared with the experi- 19 the optimized Tc-O bond distances are slightly longer.…”

“…Inspecting the optimized structure of the prototypical complex 99m Tc-MDP, the calculated Tc-O bond lengths are found to vary from 2.007 to 2.088 Å, which are generally in line with the observed Tc-O single bond lengths (2.00-2.03 Å) 30 since Tc=O double bond lengths are considerably shorter (1.65-1.70 Å). 30 Compared with the experi- 19 the optimized Tc-O bond distances are slightly longer. This is not surprising given that crystal packing and hydrogen bonds can induce conformational features that are not present in the theoretical calculation of the isolated molecule in the gas phase at 0 K. Additionally, there is also inherent drawback in the DFT calculations arising from the dynamical correlation effects.…”

trans-Dichlorobis[o-phenylenebis(dimethylarsine)]technetium(III), perchlorate and chloride salts

“…The average Tc-C1 lengths found here [C1-salt, 2-329 (1)/~; CIO~-salt, 2.318 (6) A] may be compared with recently determined values for (NH4)2[TcCI6], 2.353 (1) /~, , for [TcCI40]-, 2.31 (1)/~, (Cotton, Davison, Day, Gage & Trop, 1979) and for [TcC12(HbPz3)O], 2.328 (6) /~ (Thomas, Estes, Elder & Deutsch, 1979). Thus the Tcm-Cl bond length determined here falls within the range of those found for Tc~v-Cl and Tcv-Cl and indicates that the Tc-C1 distance does not vary systematically with oxidation state.…”

The Present Status of Technetium Chemistry

“…Tetra the HBPzJ ion. The Tc-centre is in a distorted octahedral coordination environment consisting of the oxygen, the chlorine and the three nitrogen atoms of the HBPzJ ligand [163]. The trans-dioxo(l ,4,8,11-tetraazacyclotetradecane) technetium(V) cation, trans-[Tc(cyclam)0 2 ] + , has been prepared and structurally characterized [164].…”