ACCEPTED MANUSCRIPT
Syntheses of the Schiff base ligands: L1 and L2. (E)-2-hydroxy-N'-((2-
hydroxynaphthalen-1-yl)methylene)benzohydrazide (L1) was synthesized according
to a literature procedure [23]. In brief, 2-hydroxy-1-naphthaldehyde (1.72 g, 10
mmol), 2-hydroxybenzohydrazide (1.52 g, 10 mmol) and 50 ml methanol were mixed.
After stirring 15 min at 373 K, the resulting mixture was kept in air for 1 h, affording
the title compound as a yellow colored solid. Yield: 76%. Anal. Calcd for C18H14N2O3
(306.32): C, 70.58; H, 4.61 and N, 9.15. Found: C, 70.83; H, 4.77 and N, 9.36. IR
(KBr, cm−1): 3071m, 2539m, 1618vs, 1590s, 1498vs, 1435s, 1358s, 1290s, 1211vs,
1145m, 1112m, 1077m, 1042m, 899m, 846m, 817m, 762s, 647w, 586w, 555w, 471w.
1
MS (ESI) m/z 305 ([M – H]–). H NMR (400 MHz, DMSO-d6) δ 12.75 (1H, s), 9.55
(1H, s), 8.32 (1H, d, J = 8.6 Hz), 7.94 (2H, m), 7.89 (1H, brd, J = 8.2 Hz), 7.60 (1H,
m), 7.48 (1H, m), 7.41 (1H, t, J = 7.4 Hz), 7.24 (1H, d, J = 9.0 Hz), 7.02 (2H, m); 13C
NMR (100 MHz, DMSO-d6) δ 164.0, 158.8, 158.1, 147.7, 134.0, 132.9, 131.7, 128.9,
128.8, 127.8, 127.7, 123.6, 121.0, 119.2, 118.9, 117.3, 115.7, 108.6 (Figs. S1 and S2).
The (E)-2-hydroxy-N'-(phenyl(pyridin-2-yl)methylene)benzohydrazide ligand (L2)
was synthesized by mixing equimolar amounts of 2-hydroxybenzohydrazide (1.52 g,
10 mmol) with phenyl(pyridin-2-yl)methanone (1.83 g, 10 mmol) in methanol (50
mL). The reaction mixture was refluxed on a water bath for 6 h. Then the mixture was
kept in air for a week and light yellow colored solid was obtained. Yield: 69%. Anal.
Calcd for C19H15N3O2 (317.74): C, 71.91; H, 4.76 and N, 13.24. Found: C, 71.65; H,
4.77 and N, 13.02. IR (KBr, cm−1): 3175w, 3051m, 2833w, 1645vs, 1602s, 1576s,
1485m, 1412m, 1391m, 1301w, 1331s, 1287vs, 1188s, 1161m, 957w, 818w, 793m,
1
739m, 691m, 538w, 419w. MS (ESI) m/z 316 ([M – H]–). H NMR (400 MHz,
DMSO-d6) δ 13.14 (1H, s), 8.88 (1H, s), 8.04 (1H, m), 7.98 (1H, m), 7.63 (1H, m),
7.56 (2H, m), 7.46 (3H, m), 7.38 (2H, m), 6.96 (2H, m); 13C NMR (100 MHz,
DMSO-d6) δ 162.0, 156.2, 151.6, 149.6, 149.6, 138.0, 137.1, 133.5, 131.0, 129.4,
128.4 × 2 , 128.1 × 2, 125.0, 124.7, 119.7, 117.8, 116.7 (Figs. S3 and S4).
Synthesis of [Cu(L1)(Py)] (C1). This complex was prepared by adding a
methanolic solution of L1 ligand (2 mmol) and pyridine (Py, 2 mmol) to a solution of
CuBr2 (0.44 g, 2 mmol) in anhydrous methanol, and the mixture was heated to reflux
for 2 h. The greenish-blue solution was cooled to room temperature and then filtered.
Bright green crystals suitable for X-ray crystallography were obtained on slow
evaporation of the reaction mixture over a period of 3–7 days. Yield: 73%. Anal.
5