Spectral and electrochemical halide anion recognition by acyclic ruthenium(II) 5,5′-bis-amide substituted bipyridyl receptor molecules

Reductive Couplings of 2-Halopyridines without External Ligand: Phosphine-Free Nickel-Catalyzed Synthesis of Symmetrical and Unsymmetrical 2,2′-Bipyridines

“…The product was isolated as a white solid in 81% yield (798 mg): mp > 300 °C; R f = 0.22 (petroleum ether/ethyl acetate =3:1); IR (cm –1 , KBr) 1669; 1 H NMR (400 MHz, DMSO- d 6 ) δ 10.47 (s, 2H), 8.92 (d, J = 2.2 Hz, 2H), 8.33 (dd, J = 2.4 Hz, J = 8.2 Hz, 2H), 7.74–7.69 (m, 6H), 7.36 (t, J = 7.7 Hz, 4H), 7.12 (t, J = 7.6 Hz, 2H); 13 C NMR (125 MHz, DMSO- d 6 ) δ 163.4, 153.2, 149.8, 139.5 139.1, 130.5, 129.2, 124.6, 120.9 (one carbon missing due to overlap). Data was consistent with that reported in the literature …”

Reductive Couplings of 2-Halopyridines without External Ligand: Phosphine-Free Nickel-Catalyzed Synthesis of Symmetrical and Unsymmetrical 2,2′-Bipyridines

“…The product was isolated as a white solid in 81% yield (798 mg): mp > 300 °C; R f = 0.22 (petroleum ether/ethyl acetate =3:1); IR (cm –1 , KBr) 1669; 1 H NMR (400 MHz, DMSO- d 6 ) δ 10.47 (s, 2H), 8.92 (d, J = 2.2 Hz, 2H), 8.33 (dd, J = 2.4 Hz, J = 8.2 Hz, 2H), 7.74–7.69 (m, 6H), 7.36 (t, J = 7.7 Hz, 4H), 7.12 (t, J = 7.6 Hz, 2H); 13 C NMR (125 MHz, DMSO- d 6 ) δ 163.4, 153.2, 149.8, 139.5 139.1, 130.5, 129.2, 124.6, 120.9 (one carbon missing due to overlap). Data was consistent with that reported in the literature …”

Functionalized Ruthenium Complexes: Selective “Turn‐on” Detection of Biologically Relevant Anionic Species

“…In Hepes buffered solution, this shift is even more important (for Ru 7 , 734 nm in aqueous medium). Such a phenomenon has already been observed in ruthenium complexes functionalized with amide or ester groups . The quantum yields of all the 3,3′‐functionalized complexes (1.9–2.4 %) are much lower than that of the [Ru(bipy) 3 ] 2+ standard ( Φ = 6.2 %).…”

“…As shown in Table , in acetonitrile, all the synthesized tris‐bipyridyl ruthenium complexes show two characteristic absorption bands at about 287 and 440 nm corresponding to ligand‐center (LC) and metal‐to‐ligand charge‐transfer (MLCT) transitions, respectively. Owing to the electron‐withdrawing nature of the amide substituents, which leads to lower MLCT transition energies, the MLCT absorption band is blueshifted with respect to [Ru(bipy) 3 ] 2+ ( λ max = 450 nm) …”

The Use of Electrospray Mass Spectrometry to Determine Speciation in a Dynamic Combinatorial Library for Anion Recognition

“…The problem with many 2,2′‐bipyridine amide‐functionalized ligand systems reported for the recognition of anions44 using the tris‐chelating ruthenium(II) centre is their solubility 6. 45 To overcome this problem, and the possibility that inter‐ligand steric interactions can dominate larger ligand systems around the iron(II) centre, 5‐benzylamido‐2,2′‐pyridine (L1, Figure 1) was selected with the aromatic group separated from the amide by a flexible methylene spacer, and only one functional group per ligand. This ligand system has previously been shown to have a good response to the introduction of anions in the complex mer‐ and fac ‐[Ru(L1) 3 ] 2+ 8…”

Reductive Couplings of 2-Halopyridines without External Ligand: Phosphine-Free Nickel-Catalyzed Synthesis of Symmetrical and Unsymmetrical 2,2′-Bipyridines

“…The product was isolated as a white solid in 81% yield (798 mg): mp > 300 °C; R f = 0.22 (petroleum ether/ethyl acetate =3:1); IR (cm –1 , KBr) 1669; 1 H NMR (400 MHz, DMSO- d 6 ) δ 10.47 (s, 2H), 8.92 (d, J = 2.2 Hz, 2H), 8.33 (dd, J = 2.4 Hz, J = 8.2 Hz, 2H), 7.74–7.69 (m, 6H), 7.36 (t, J = 7.7 Hz, 4H), 7.12 (t, J = 7.6 Hz, 2H); 13 C NMR (125 MHz, DMSO- d 6 ) δ 163.4, 153.2, 149.8, 139.5 139.1, 130.5, 129.2, 124.6, 120.9 (one carbon missing due to overlap). Data was consistent with that reported in the literature …”

Functionalized Ruthenium Complexes: Selective “Turn‐on” Detection of Biologically Relevant Anionic Species

“…In Hepes buffered solution, this shift is even more important (for Ru 7 , 734 nm in aqueous medium). Such a phenomenon has already been observed in ruthenium complexes functionalized with amide or ester groups . The quantum yields of all the 3,3′‐functionalized complexes (1.9–2.4 %) are much lower than that of the [Ru(bipy) 3 ] 2+ standard ( Φ = 6.2 %).…”

“…As shown in Table , in acetonitrile, all the synthesized tris‐bipyridyl ruthenium complexes show two characteristic absorption bands at about 287 and 440 nm corresponding to ligand‐center (LC) and metal‐to‐ligand charge‐transfer (MLCT) transitions, respectively. Owing to the electron‐withdrawing nature of the amide substituents, which leads to lower MLCT transition energies, the MLCT absorption band is blueshifted with respect to [Ru(bipy) 3 ] 2+ ( λ max = 450 nm) …”

The Use of Electrospray Mass Spectrometry to Determine Speciation in a Dynamic Combinatorial Library for Anion Recognition

“…The problem with many 2,2′‐bipyridine amide‐functionalized ligand systems reported for the recognition of anions44 using the tris‐chelating ruthenium(II) centre is their solubility 6. 45 To overcome this problem, and the possibility that inter‐ligand steric interactions can dominate larger ligand systems around the iron(II) centre, 5‐benzylamido‐2,2′‐pyridine (L1, Figure 1) was selected with the aromatic group separated from the amide by a flexible methylene spacer, and only one functional group per ligand. This ligand system has previously been shown to have a good response to the introduction of anions in the complex mer‐ and fac ‐[Ru(L1) 3 ] 2+ 8…”

Reductive Couplings of 2-Halopyridines without External Ligand: Phosphine-Free Nickel-Catalyzed Synthesis of Symmetrical and Unsymmetrical 2,2′-Bipyridines

“…The product was isolated as a white solid in 81% yield (798 mg): mp > 300 °C; R f = 0.22 (petroleum ether/ethyl acetate =3:1); IR (cm –1 , KBr) 1669; 1 H NMR (400 MHz, DMSO- d 6 ) δ 10.47 (s, 2H), 8.92 (d, J = 2.2 Hz, 2H), 8.33 (dd, J = 2.4 Hz, J = 8.2 Hz, 2H), 7.74–7.69 (m, 6H), 7.36 (t, J = 7.7 Hz, 4H), 7.12 (t, J = 7.6 Hz, 2H); 13 C NMR (125 MHz, DMSO- d 6 ) δ 163.4, 153.2, 149.8, 139.5 139.1, 130.5, 129.2, 124.6, 120.9 (one carbon missing due to overlap). Data was consistent with that reported in the literature …”

Functionalized Ruthenium Complexes: Selective “Turn‐on” Detection of Biologically Relevant Anionic Species

“…In Hepes buffered solution, this shift is even more important (for Ru 7 , 734 nm in aqueous medium). Such a phenomenon has already been observed in ruthenium complexes functionalized with amide or ester groups . The quantum yields of all the 3,3′‐functionalized complexes (1.9–2.4 %) are much lower than that of the [Ru(bipy) 3 ] 2+ standard ( Φ = 6.2 %).…”

“…As shown in Table , in acetonitrile, all the synthesized tris‐bipyridyl ruthenium complexes show two characteristic absorption bands at about 287 and 440 nm corresponding to ligand‐center (LC) and metal‐to‐ligand charge‐transfer (MLCT) transitions, respectively. Owing to the electron‐withdrawing nature of the amide substituents, which leads to lower MLCT transition energies, the MLCT absorption band is blueshifted with respect to [Ru(bipy) 3 ] 2+ ( λ max = 450 nm) …”

The Use of Electrospray Mass Spectrometry to Determine Speciation in a Dynamic Combinatorial Library for Anion Recognition

“…The problem with many 2,2′‐bipyridine amide‐functionalized ligand systems reported for the recognition of anions44 using the tris‐chelating ruthenium(II) centre is their solubility 6. 45 To overcome this problem, and the possibility that inter‐ligand steric interactions can dominate larger ligand systems around the iron(II) centre, 5‐benzylamido‐2,2′‐pyridine (L1, Figure 1) was selected with the aromatic group separated from the amide by a flexible methylene spacer, and only one functional group per ligand. This ligand system has previously been shown to have a good response to the introduction of anions in the complex mer‐ and fac ‐[Ru(L1) 3 ] 2+ 8…”