Synthesis and Characterization of Vanadium Complex

Complex 1 (100 mg, 0.1005 mmol)
was dissolved in 15 mL of quinoline, and CuCN (900 mg, 10.05 mmol,
ca. 100 equiv.) was added. The reaction mixture was stirred for 10
min and then heated with stirring at 190 °C for 3 h under an
argon atmosphere. The reaction mixture was cooled to ambient temperature
and filtered using a G-4 crucible. The filtrate was diluted with chloroform
(30 mL) and washed with 10 M HCl solution (3 × 25 mL) followed
by water (3 × 25 mL). After drying the chloroform layer with
sodium sulfate, the solvent was removed by a rotary evaporator. The
crude product was dissolved in chloroform and purified over silica
(100–200 mesh) using chloroform as the eluent. The last and
major band of three fractions was collected and identified as 2. Complex 2 was obtained in pure form by rotatory
evaporation of the solvent. Yield 32% (25 mg, 0.0321 mmol). UV–vis
(CH₂Cl₂): λ_max (nm) (log ε):
443 (5.31), 578 (3.81), 625 (4.67). MALDI-TOF-MS (m/z): found 779.53 [M]⁺, calcd. 779.15.
Anal. calcd. for C₄₈H₂₄N₈OV: C, 73.94;
H, 3.10; N, 14.37. Found: C, 73.75; H, 3.01; N, 14.22.