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added. The solution was stirred at ambient temperature overnight.
The formed precipitate was removed by filtration and recrystallized
from EtOH or iPrOH.
1045 (CꢀO), 919, 887, 799 cmꢀ1; ESI-MS: m/z: calcd: 555.1; found:
555.2 [Ti2L2 (OEt)4+Na]+.
2
[{TiL3(OEt)2}x] (4): 1,3-Cyclohexanedioxime (94 mg, 0.66 mmol) was
dissolved in ethanol (6 mL) and heated to reflux to dissolve the
ligand, followed by dropwise addition of Ti(OEt)4 (0.14 mL,
0.66 mmol). The solution was stirred for 30 min at room tempera-
ture, while a red-brownish precipitate of 4 was formed, which was
collected by filtration. 13C CP-MAS NMR: d=143.0 (CH2CNCH2), 68.7
(OCH2CH3), 16.5 ppm (CH2CH2C, CH2CH2CH2, CNCH2CN, OCH2CH3);
15N CP-MAS NMR: d=274.0 ppm.
L1H2: yield: 75 mmol (86%); 1H NMR (250 MHz, [D6]DMSO, 258C,
TMS): d=10.3 (s, 2H; NꢀOH), 2.25 (s, 4H; CH2CH2CN), 1.69 ppm (s,
6H; CH3CN); 13C NMR (62.86 MHz, [D6]DMSO, 258C, TMS): d=155.3
(CH3CNCH2), 32.5 (CNCH2CH2), 13.5 ppm ((CH3)2CN).
L2H2: yield: 78 mmol (90%); 1H NMR (250 MHz, [D6]DMSO, 258C):
d=10.77 (s, 2H; NꢀOH), 6.64 (s, 2H; CH=N), 2.20 (t, 4H;
CH2CH2CN), 1.54 ppm (m, 2H; CH2CH2CH2); 13C NMR (62.86 MHz,
[D6]DMSO, 258C, TMS): d=150.5 (CHNCH2), 25.7 (CNCH2CH2),
23.0 ppm (CH2CH2CH2).
[{TiL4(OEt)2}x] (5): 1,4-Cyclohexanedioxime (94 mg, 0.66 mmol) was
dissolved in ethanol (6 mL), heated to reflux to dissolve the ligand,
followed by dropwise addition of Ti(OEt)4 (0.14 mL, 0.66 mmol).
The solution was stirred for 30 min at room temperature, while
a white precipitate of 5 was formed, which was collected by filtra-
tion. IR (ATR): n˜ =2967 (CꢀH), 2926 (CꢀH), 1653 (C=N), 1437 (CꢀC),
1374 (CꢀOꢀTi), 1359, 1327, 1122 (CꢀO), 996 (CꢀO), 943, 849,
L3H2: yield: 84 mmol (97%); 1H NMR (250 MHz, [D6]DMSO, 258C,
TMS): d=10.42 (s, 2H; NꢀOH), 3.42 (s, 2H; CNCH2CN), 2.29 (t, 4H;
CNCH2CH2), 1.62 ppm (m, 2H; CH2CH2CH2); 13C NMR (62.86 MHz,
[D6]DMSO, 258C, TMS): d=153.6 ((CH2)2CN), 31.0 (CH2CH2C), 24.4
(CCH2C), 23.7 ppm (CH2CH2CH2); 13C CP-MAS NMR: d=152.9
(CH2CNCH2), 31.4 ppm (CH2CH2C, CH2CH2CH2, CNCH2CN); 15N CP-
MAS NMR: d=278.8 ppm.
824 cmꢀ1
.
[{TiL5(OiPr)2}2] (6): L5H2 (214 mg, 0.66 mmol) was dissolved in 1,2-
dichloroethane (3 mL), and Ti(OiPr)4 (0.2 mL, 0.66 mmol) was added
dropwise. The yellow solution was stirred for 20 min at room tem-
perature. Removing the solvent under vacuum resulted in a solid
[11]
L4H2: yield: 85 mmol (98%); 1H NMR (250 MHz, [D6]DMSO, 258C,
TMS): d=10.33 (s, 2H; NꢀOH), 2.43 (t, 4H; CH2), 2.34 ppm (t, 4H;
CH2); 13C NMR (62.86 MHz, [D6]DMSO, 258C, TMS): d=156.6
((CH2)2CN), 26.9 (CH2CH2C), 23.9 ppm (CH2CH2C); 13C CP-MAS NMR:
d=157.8 (CH2CNCH2), 36.5 (CH2CH2C), 24.6 ppm (CH2CH2C); 15N CP-
MAS NMR: d=278.1, 221.4 ppm (C=N···HOꢀN).
1
residue. H NMR (250 MHz, CDCl3, 258C, TMS): d=7.92 (s, 4H; CH=
N), 7.25 (d, 2H; arylꢀH), 7.14 (m, 2H; arylꢀH), 6.73 (m, 4H; arylꢀH),
4.63 (m, 2H; (CH3)2CH), 4.47 (m, 2H; (CH3)2CH), 3.18 (t, 8H;
CNCH2CH2), 1.23 (d, 24H; (CH3)2CH), 1.03 ppm (m, 16H;
CH2CH2CH2); 13C NMR (62.86 MHz, CDCl3, 258C, TMS): d=164.3
(arylꢀCHN), 163.8 (arylꢀCO), 134.2 (arylꢀCH), 133.2 (arylꢀCH), 122.2
(arylꢀCꢀCHN), 118.8 (arylꢀCH), 117.0 (arylꢀCH), 77.9/76.0 ((CH3)2CH),
62.2 (CNCH2CH2), 31.3 (CH2CH2CH2), 26.9 (CH2CH2CH2), 26.5/
Synthesis of the complexes
[{TiL1(OiPr)2}2] (1): 2,5-Hexanedioxime (95 mg, 0.66 mmol) was dis-
solved in 1,2-dichloroethane (3 mL) and Ti(OiPr)4 (0.2 mL,
0.66 mmol) was added dropwise. The solution was stirred for
30 min at room temperature. Colorless crystals of 1 (152 mg, 75%)
were obtained after two weeks by slow evaporation of the solvent.
1H NMR (250 MHz, CDCl3, 258C, TMS): d=4.47 (m, 2H; (CH3)2CH),
3.37 (m, 2H; (CH3)2CH), 3.12 (m, 4H; CH2CH2CN), 2.12 (m, 4H;
CH2CH2CN), 1.82 (s, 12H; CH3CN), 1.28 (d, 12H; (CH3)2CH), 1.17 ppm
(d, 12H; (CH3)2CH); 13C NMR (62.86 MHz, CDCl3, 258C, TMS): d=
144.8 (CH3CNCH2), 77.1/75.9 ((CH3)2CH), 30.5 (CNCH2CH2), 26.2/25.7
((CH3)2CH), 19.9/17.0 ppm (CH3CN); IR (ATR): n˜ =2967 (CꢀH), 2918
(CꢀH), 1658 (C=N), 1428 (CꢀC), 1360 (CꢀOꢀTi), 1121 (CꢀO), 995 (Cꢀ
25.3 ppm ((CH3)2CH); ESI-MS: m/z: calcd: 999.4; found: 999.5 [Ti2L5 -
2
(OiPr)4+Na]+; calcd: 775.3; found: 775.4 [(TiL5 )iPrOH+Na]+; calcd:
2
511.2; found: 511.2 [TiL5(OiPr)2+Na]+; calcd: 307.1; found: 307.1 [Ti-
(OiPr)4+Na]+.
[{ZrL5(OiPr)2}2] (7) was synthesized analogously by reacting Zr-
(OiPr)4·iPrOH with L5H2 in toluene. 1H NMR (250 MHz, C6D6, 258C,
TMS): d=7.83 (s, 4H; CH=N), 7.30 (d, 2H; arylꢀH), 7.19–7.05 (m,
4H; arylꢀH), 6.73 (m, 2H; arylꢀH), 4.63 (m, 4H; (CH3)2CH), 3.42 (t,
8H; CNCH2CH2), 1.86 (m, 8H; CH2CH2CH2), 1.48 (d, 24H; (CH3)2CH),
1.16 ppm (m, 8H; CH2CH2CH2); 13C NMR (62.86 MHz, C6D6, 258C,
TMS): d=167.0 (arylꢀCHN), 163.7 (arylꢀCO), 134.6 (arylꢀCH), 134.2
(arylꢀCH), 122.4 (arylꢀCꢀCHN), 120.3 (arylꢀCH), 117.0 (arylꢀCH),
71.4 ((CH3)2CH), 62.8 (CNCH2CH2), 31.3 (CH2CH2CH2), 26.7 ((CH3)2CH),
21.8 ppm (CH2CH2CH2); ESI-MS: m/z: calcd: 1095.3; found: 1095.3
[Zr2L5 (OiPr)4+Cl]ꢀ; calcd: 1083.3; found: 1083.4 [Zr2L5 (OiPr)4+Na]+
O), 934, 849, 819 cmꢀ1
.
[{TiL1(OEt)2}2] (2) was synthesized similarly from Ti(OEt)4 with etha-
nol as the solvent. 1H NMR (250 MHz, CDCl3, 258C, TMS): d=4.35
(q, 4H; CH3CH2), 3.91 (q, 4H; CH3CH2), 2.77/2.57 (s, 8H; CH2CH2CN),
1.98 (s, 12H; CH3CN), 1.45/1.21/0.94 ppm (d, 12H; CH3CH2);
13C NMR (62.86 MHz, CDCl3, 258C, TMS): d=146.0 (CH3CNCH2),
71.0/70.1 (CH3CH2), 30.7 (CNCH2CH2), 19.0/18.0 (CH3CH2), 16.7/
2
2
.
[{TiL6(OiPr)2}2] (8): L6H2 (228 mg, 0.66 mmol) was dissolved in 1,2-
dichloroethane (3 mL) and Ti(OiPr)4 (0.2 mL, 0.66 mmol) was added
dropwise. The yellow solution was stirred for 20 min at room tem-
perature. Removing the solvent under vacuum resulted in a solid
[11]
13.1 ppm (CH3CN); ESI-MS: m/z: calcd: 583.2; found: 583.2 [Ti2L1 -
2
(OEt)4+Na]+.
[{TiL2(OEt)2}2] (3): 1,5-Pentanedioxime (86 mg, 0.66 mmol) was dis-
solved in ethanol (3 mL), and Ti(OEt)4 (0.14 mL, 0.66 mmol) was
added dropwise. The solution was stirred for 30 min at room tem-
perature. Colorless crystals of 3 (112 mg, 61%) were obtained after
1
residue. H NMR (250 MHz, CDCl3, 258C, TMS): d=7.70 (s, 4H; CH=
N), 7.36 (d, 4H; arylꢀH), 7.00 (d, 4H; arylꢀH), 6.80–6.70 (m, 16H;
arylꢀH), 4.51 (m, 4H; (CH3)2CH), 4.00 (s, 8H; CNCH2aryl), 1.26 ppm
(d, 12H; (CH3)2CH); 13C NMR (62.86 MHz, CDCl3, 258C, TMS): d=
165.8 (arylꢀCHN), 164.0 (arylꢀCO), 137.2 (arylꢀC), 134.4 (arylꢀCH),
133.7 (arylꢀCH), 129.6 (arylꢀC), 127.0 (arylꢀCH), 122.2 (arylꢀCꢀ
CHN), 118.9 (arylꢀCH), 117.1 (arylꢀCH), 78.0 ((CH3)2CH), 76.2
((CH3)2CH), 63.6 (CNCH2CH2), 26.5 ((CH3)2CH), 25.1 ppm ((CH3)2CH);
1
two weeks by slow evaporation of the solvent. H NMR (250 MHz,
CDCl3, 258C, TMS): d=4.34 (m, 4H; CH3CH2), 3.64 (m, 4H; CH3CH2),
2.50 (t, 8H; CH2CH2CN), 1.84 (m, 4H; CH2CH2CH2), 1.16/0.84 ppm (d,
12H; CH3CH2); 13C NMR (62.86 MHz, CDCl3, 258C, TMS): d=139.4
(CHNCH2), 71.7/68.2 (CH3CH2), 58.3 (CNCH2CH2), 27.9 (CH2CH2CH2),
22.2/18.0 ppm (CH3CH2); IR (ATR): n˜ =2966 (CꢀH), 2919, 2859 (Cꢀ
H), 1631 (C=N), 1437 (CꢀC), 1374 (CꢀOꢀTi), 1114 (CꢀO), 1095, 1069,
ESI-MS: m/z: calcd: 1039.4; found: 1039.3 [Ti2L6 (OiPr)4+Na]+;
2
calcd: 957.3; found: 957.3 [Ti2L6 (OiPr)3]+.
2
ꢁ 2013 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
ChemPlusChem 2013, 78, 343 – 351 350