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temperature, followed by dissolution in hot methanol. The resulting hot violet solution was
filtered, while hot to remove small quantities of undissolved residue and then cooled to
room temperature. Violet single crystals suitable for X-ray analysis were obtained from
the resultant solution after 1 day. Yield: 67.5%. Color: light blue. Anal (%), Calcd for
C22H22N4O12ClCuNi: C, 36.31; H, 3.03; N, 7.70. Found: C, 36.72; H, 3.00; N, 7.81. Mass (m/z): expt.
(527.19 and 531.93) theo. (528.06, 530.06). Molar conductance (Ω−1 mol−1 cm2): 230. Magnetic
Moment (μB): 2.92 B.M, Electronic spectrum [λmax, nm (εmax, dm3 mol−1 cm−1)]: in MeCN, 670
(252). IR data (cm−1, KBr): 1560 s, vas(COO); 1444s (vsCOO), 1142 s, 1116 s, 1091s v(ClO4), 771 s
(out-of-plane ring deformation mode of 2,2′-bipyridine), 683 m (in-plane ring deformation
mode. EPR: g|| = 2.140, g⊥ = 2.064, gav = 2.089; Cyclic voltammogram (Epc mV s−1): −0.29, −0.54
and -0.70 V: (Epa mV s−1): −0.23 and −0.40 V.
2.3. Procedure for oxidation of benzylic alcohols by [CuNi(μ-OAc)(μ-OH)(μ-OH2)
(bpy)2](ClO4)2
To a mixture of benzyl alcohol (0.5 mL, 4.64 mmol) and 15% aqueous hydrogen peroxide
(1.1 mL, 4.85 mmol), the catalyst [CuNi(μ-OAc)(μ-OH)(μ-OH2)(bpy)2](BF4)2 (8 mg, 0.01 mmol)
was added and stirred at 70 °C for 5 h. The organic and aqueous phase were separated by a
separating funnel and then purified by column chromatography to afford benzaldehyde.
The identity of the benzaldehyde was ascertained by comparison with authentic sample
using IR, 1H NMR, and 13C NMR.
2.3.1. Characterization data for benzaldehyde
1
Colorless liquid; Yield: 93%; H (400 MHz, CDCl3): δ 9.96 (s, 1H), 7.87–7.41 (m, 5H); 13C
(100 MHz, CDCl3): δ 192.5, 136.2, 134.4, 129.8, 128.9; IR (KBr): 1702 cm−1.
2.4. Oxidation of benzyl alcohol under anaerobic condition
Benzyl alcohol (0.5 mL, 4.64 mmol) and the catalyst ([CuNi(μ-OAc)(μ-OH)(μ-OH2)(bpy)2](BF4)2
(8 mg, 0.01 mmol) were mixed together in a round bottom flask. To this reaction mixture
15% H2O2 (1.1 mL, 4.85 mmol) was added and the resulting reaction mixture was stirred for
5 h under dinitrogen. The organic and aqueous phases were separated in the usual way. The
identity of the product was ascertained with authentic sample by usual spectroscopic meth-
ods. Benzaldehyde, yield: (97%, GC).
3. Results and discussion
The heterobimetallic complex [CuNi(μ-OH)(μ-OH2)(μ-OAc)(bpy)2](ClO4)2 was prepared by
heating a mixture of Cu(OAc)2·H2O, Ni(OAc)2·4H2O, 2,2′-bipyridine and NaClO4 in air in an
electronic oven at 150 °C for 5 h followed by dissolution in methanol, and crystallizing over-
night at room temperature. The complex is violet, clearly different from the color of constit-
uent metal ions.
All relevant data and figures regarding the characterization of the crystal are found in
Tables 1, S1 and S2 and Figures 1, S1 and S2. The complex consists of dinuclear [CuNi(μ-OH)
(μ-OH2)(μ-OAc)(bpy)2]2+ cation and two well separated perchlorate anions (Figure 1). The
molecular formula and packing diagram of the complex is shown in Figures S1 and S2. In