Rhenium Complexes Based on an N2O Tridentate Click Scaffold: From Synthesis, Structural and Theoretical Characterization to a Radiolabelling Study. Issue 1 (29th November 2016)

• Record Type: Journal Article
• Authors: Eychenne, Romain; Guizani, Sihem; Wang, Jin‐Hui; Picard, Claude; Malek, Nadia; Fabre, Paul‐Louis; Wolff, Mariusz; Machura, Barbara; Saffon, Nathalie; Lepareur, Nicolas; Benoist, Eric
• Is Part Of: European journal of inorganic chemistry. Issue 1(2017)
• Page Start: 69
• Page End: 81
• Publication Date: 2016-11-29
• Subjects: Rhenium -- N, O lignds -- Radiopharmaceuticals -- Click chemistry -- X‐ray diffraction -- Chelates; Chemistry, Inorganic -- Periodicals; Organometallic chemistry -- Periodicals; Bioinorganic chemistry -- Periodicals; Solid state chemistry -- Periodicals; 546
• DOI: 10.1002/ejic.201600877
• Languages: English
• ISSNs: 1434-1948

Abstract

Abstract : A general synthetic approach to a novel range of semirigid bifunctional chelating agents (BCAs) that include an aromatic ring and a triazolyl moiety in the chelating unit has been investigated for the fac ‐[M(CO)3 ] + core (M = 185/187 Re or 188 Re). The strategy includes the facile preparation of these N2 O ligands bearing various functionalized arms (carboxylate, terminal alkyne, aromatic amine). The reaction of commercial [Re(CO)5 Cl] {or a freshly prepared [Re(OH2 )3 (CO)3 ] + precursor} with our BCAs in methanol led to the formation of stable neutral tricarbonylrhenium complexes of general formula [Re(CO)3 (L)] (LH =5, 10, 11 ) in high yields. These compounds were characterized by IR and NMR spectroscopy, mass spectrometry, electrochemistry, and X‐ray crystallography for [Re(CO)3 (5 –H )] and [Re(CO)3 (11 –H )] as well as by DFT calculations. The analogous rhenium‐188 complexes [ 188 Re(CO)3 (5 )] and [ 188 Re(CO)3 (11 –H )] were also prepared, in acceptable to excellent yields, by the reaction of5 or11 with the fac ‐[ 188 Re(OH2 )3 (CO)3 ] + precursor in methanol at 80 °C. The structural identities of the radioactive complexes were assessed by HPLC studies. The good affinity of these click ligands for the Re I core combined with the ease of their derivatization make this chelating system promising for the conception of target‐specific radiopharmaceuticals for therapeutic purposes. Abstract : Novel tricarbonylrhenium complexes of the general formula [Re(CO)3 (L)], in which LH is an N2 O tridentate click ligand, have been prepared and fully characterized, including by X‐ray crystallography and DFT calculations. The analogous [ 188 Re(CO)3 (L)] complexes were also investigated and their structures established by HPLC. This study shows the great potential of tripodal click scaffolds for 188 Re I .