Tricarbonyl Re^I Complexes from Functionalised Pyridine–Triazole Derivatives: From Mononuclear to Unexpected Dimeric Complexes

Abstract

As a variation of the commonly used bipy ligand in Re(CO) 3 chemistry, a series of structurally related complexes in which bipy is replaced by pyridine-triazole ligands (or pyta) bearing a pendant acetyl group on the triazole ring were prepared efficiently by the click chemistry approach. Depending on the nature of the pendant arm, different Re I complexes were obtained. Surprisingly, starting from the ligand with unprotected acetyl group yielded two structural isomers of Re(CO) 3 dimeric species. One isomer (compound 5a) was iso-

Luminescent sensor for copper(II) ion based on imine functionalized monometallic rhenium(I) complexes

“…No imaginary frequency was seen in the optimized geometry and this indicates the structure obtained corresponds to a minimum on the potential energy surface. Selected bond lengths and bond angles are shown in Table 1 and they are consistent with other rhenium complexes having similar structure [53]. It can be seen that Re1-C2 bond length in axial position is shorter than Re1-C3 and Re1-C4 bond lengths in equatorial positions.…”

Synthesis, structure and luminescent properties of rhenium(I) carbonyl complexes containing pyrimidine-functionalized N-heterocyclic carbenes

“…The low-energy broad bands at 369, 359, 356, and 359 nm for 1-4, respectively, are assigned to a metal-to-ligand charge-transfer transition (MLCT) (dπ(Re)-π*(pyrimidine-NHC)), similar to those of the analogous Re(I) carbonyl12 complexes of the reported complexes, such as [Re(CO) 3 (bipy)Cl][48] (λ max 371 nm), and [Re(CO) 3 (py-NHC)Cl][35] (λ max 355 nm).As shown inFig. 3, the excitation at the MLCT absorption region (~420 nm) of complexes 1-4 in the deaerated CH 2 Cl 2 solution leads to broad emissions centered at 555-570 nm, respectively, the characteristic MLCT emissions of Re I complexes[49].In the solid state, the emission spectra of 1-4 centered at 515-532 nm, blue shifted by about 50 nm in comparison to those of the solution samples.…”

Click Synthesis and Redox Chemistry of Mono‐ and Heterobimetallic Triazolyl and Triazolium‐Ferrocene and Cobalticinium Complexes

“…[1] The Cu Icatalyzed regioselective azide-alkyne cycloaddition (CuAAC), [2,3] which is presently the most frequent example, [4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22] was reported in 2002 by the research groups of Sharpless et al [2] and Meldal et al [3] This synthetic advantage is not the only one, since the resulting 1,2,3-triazolyl derivatives that are selectively produced are also good ligands in a variety of transition-metal complexes that have new luminescent, [23][24][25][26] sensor, [27][28][29] or catalytic properties. proposes to easily assemble molecular fragments.…”