Probing for missing links in the binary and ternary V(V)–citrate–(H2O2) systems: Synthetic efforts and in vitro insulin mimetic activity studies

A journey into the electrochemistry of vanadium compounds

“…Later the same research group [179] 2 ] species. The cyclic voltammogram of both complexes in aqueous solution presented ill-defined electrochemical behavior, related to irreversible sequential V(V) → V(IV) and V(IV) → V(III) redox processes.…”

Vanadium(v) complexes of mandelic acid

“…In spite of the fact that the aqueous mandelic acid-vanadate system is prone to redox reactions, we succeeded in the synthesis of new vanadium(V) mandelato complexes by crystallization at Calculated wavenumbers with rel. intensity in parentheses Experimental wavenumbers Band assignment with PED 3096 (9) 2962 m n(C-H) ar 92% 3080 (11) 2888 m n(C-H) ar 92% 1653 (9) n(CQO) un 83% 1651 (100) 1659 vs n(CQO) un 83% 1299 (12) 1336 m-s d(HCC) ar 64% 1293 (52) 1323 s n(CQO) co 66% 1082 (11) 1084 m n(C-O) h 37% d(HCC) ar 21% 1051 (15) 1059 s n(C-O) h 37% d(HCC) ar 21% 968 (17), 964 (10), 953 (16), 951 (21) 928 vs n(VQO) 91% (mean) 768 (8) 765 s d(OCO) 26% 705 (11) 696 m tors(HCCC) ar 36%, tors(CCCC) ar 18% 675 (5) 622 w tors(HCCC) ar 44%, tors(CCCC) ar 39% 556 (6) 537 w d(OC h C c ) ar 23%, n(C c -C h ) 12% 420 (15) 444 s…”

“…6 The dominant components in the vanadate-a-hydroxycarboxylic acid system, apart from common vanadates, are the dinuclear and trinuclear complexes of the composition V 2 L 2 and V 3 L 2 (L = anion of the a-hydroxycarboxylic acid) accompanied by a mononuclear complex VL. 7 Several dinuclear vanadium(V) complexes with a-hydroxycarboxylato ligands were also reported in the solid state: 8,9 13 and Cs 2 [V 2 O 4 ((S)-lact) 2 ]Á2H 2 O 10 ‡ and a richer series of vanadium complexes with a-hydrocarboxylic acids with more than one carboxyl group such as malic, 14 citric, [15][16][17][18][19][20][21][22][23] homocitric 24 and tartaric acid. [25][26][27][28] The crystal structures confirmed the composition and geometry as were proposed by 51 V NMR spectroscopy; however, the V 3 L 2 complexes do not have a model compound with a solved crystal structure.…”

Vanadium and molybdenum peroxides: synthesis and catalytic activity in oxidation reactions

“…This is true also with more complicated, often polynuclear, structures: see, as just a few examples, complexes 10, 39 and related structures. [32][33][34]48,55 A review with a collection of salient UV-vis data for monoperoxo vanadium species recently appeared. 27 Quite different is the scenario of the 51 V-NMR chemical shifts, related data are collected in Table 2.…”