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CH), 7.26 (m, 2H, B-Im CH), 7.41 (m, 1H, Py CH-5), 7.58 (m, 1H, Py
CH-3), 7.64 (m, 1H, Ph CH), 7.72 (m, 1H, Ph CH-2), 7.84 (m, 1H, Py
CH-4), 7.98 (m, 1H, Ph CH), 8.07 (m, 1H, Ph CH), 8.15 (m, 1H, Py
CH-6), 12.85 ppm (s, 1H, B-Im NH).
Synthesis of Cu complexes
OTf
[
(L2)Cu]OTf (2 ): The reaction of L2 (50 mg, 0.122 mmol) and
[
Cu(MeCN) ]OTf (46 mg, 0.122 mmol) in THF (2 mL) led to the pre-
4
cipitation of a light yellow solid, which was isolated by filtration
and washed with THF (2 mL) and diethyl ether (2 mL). After drying,
1
-(2-Pyridylcarbonyl)-2-(2-methyl)benzimidazolylphenol
(III):
Compound II (6.3 g, 0.0176 mol) was suspended in THF (15 mL)
and treated with NaH (760 mg, 32 mmol). This mixture was stirred
for 40 min, and afterwards MeI (2.0 mL, 32 mmol) was added.
OTf
1
2
(72 mg, 0.116 mmol, 95%) was isolated. H NMR (400 MHz,
CD CN): d=3.10 (s, 3H, OCH ), 3.65 (s, 6H, Ph-Im NCH , Im NCH ),
3
3
3
3
6
.73 (brm, 2H, Im CH-5), 7.21 (m, 1H), 7.33 (m, 3H, Ph CH), 7.44
Then, ethanol/2-propanol (2/1, 2 mL) and H O (200 mL) were
2
(
(
m, 4H), 7.61 (m, 2H), 7.96 ppm (m, 2H); IR (KBr): 3130 (w), 3067
w), 2962 (m), 2907 (w), 1591 (m), 1480 (m), 1473 (m), 1462 (m),
added. After 3 min a white solid had formed, which was collected
by filtration, dissolved in dichloromethane (5 mL), and dried with
1
450 (m), 1434 (m), 1409 (m), 1263 (vs), 1225 (m), 1165 (m), 1155
MgSO . After layering the product solution with hexane, III was iso-
4
(
(
m), 1111 (m), 1086 (m), 1059 (m), 1030 (vs), 983 (m), 929 (w), 819
m), 787 (m), 754 (m), 638 (s), 618 (m), 573 (w), 517 cm (m); ESI-
1
lated as a white solid (2.9 g, 0.0092 mol, 52%). H NMR (400 MHz,
ꢀ
1
CDCl ): d=3.76 (s, 3H, B-Im CH ), 6.93 (m, 1H, B-Im CH), 7.11 (m,
3
3
+
MS (+ve, MeCN): m/z=472.1079 (calcd for [LCu] : 472.1199); ele-
mental analysis calcd (%) for C H CuF N O S (622.10 gmol ): C
3
1
H, B-Im CH), 7.17 (d, 2H, J =4.0 Hz, B-Im CH), 7.44–7.51 (m, 2H,
H,H
Py CH-5 and CH-3), 7.59 (d, 1H, J =8.4 Hz, Ph CH), 7.66 (m, 2H,
Ph CH and Py CH-5), 7.85 (d, 1H, J =8.0 Hz Ph CH), 7.92 (m, 1H,
Ph CH), 8.17 ppm (d, 1H, J =4.0 Hz Py CH-6); C NMR (CDCl3):
ꢀ1
3
26 23
3
5
4
H,H
5
3
0.20, H 3.73, N 11.26, S 5.15; found: C 50.35, H 3.68, N 11.32, S
.75.
3
H,H
3
13
H,H
PF6
d=31.1 (NCH ), 109.1 (B-Im CH), 119.5 (B-Im CH), 121.9 (B-Im CH),
[(L2)Cu]PF
[Cu(MeCN)
6
(2 ): The reaction of L2 (80 mg, 0.195 mmol) and
3
1
1
1
1
22.6 (B-Im CH), 123.3 (Ph CH), 125.2 (Py CH-5), 129.3 (Ph CH),
4
]OTf (73 mg, 0.195 mmol) in THF (6 mL) led to the pre-
29.7 (Py CH-3/4), 130.5 (Ph C ), 130.7 (Ph CH), 130.7 (Py CH-3/4),
cipitation of a light yellow solid, which was isolated by filtration
q
35.6 (Ph CH), 136.2 (B-im C -9), 139.6 (Ph C ), 142.6 (B-Im C -4),
and washed with THF (2 mL) and diethyl ether (2 mL). After drying,
q
q
q
PF6
47.0 (Py CH-6), 152.4 (B-Im C -2), 154.5 (Py C -2), 195.6 ppm
2
(111 mg, 0.180 mmol, 92%) was isolated. Crystals suitable for
q
q
(
C=O).
single-crystal X-ray diffraction studies could be obtained by layer-
PF6
1
ing an acetonitrile solution of 2
with diethyl ether. H NMR
Alcohol precursor of L2, IV: nBuLi (2.5m in hexane, 3.6 mL) was
added at ꢀ788C to a solution of N-methylimidazole (0.72 mL) in
THF (10 mL). After stirring at this temperature for 1.5 h, the reac-
tion mixture was transferred to a solution of III (2.9 g) in THF
(
400 MHz, CD CN): d=3.10 (s, 3H, OCH ), 3.65 (s, 6H, Ph-Im NCH ,
3
3
3
Im NCH ), 6.73 (brm, 2H, Im CH-5), 7.21 (m, 1H), 7.33 (m, 3H, Ph
3
CH), 7.44 (m, 4H), 7.61 (m, 2H), 7.96 ppm (m, 2H); IR (KBr): 3133
(
1
w), 2960 (w), 2841 (w), 1593 (m), 1481 (m), 1476 (m), 1463 (m),
452 (m), 1432 (m), 1403 (m), 1284 (w), 1227 (w), 1163 (m), 1112
m), 1087 (m), 1059 (m), 1005 (w), 982 (w), 929 (w), 877 (m), 840
(
15 mL). The mixture became dark green. It was warmed to RT,
neutralized with HCl (2m), and treated with a saturated NaCl solu-
tion (10 mL). The organic layer was separated and the aqueous
layer extracted twice with dichloromethane (3 mL). The combined
organic layers were dried with MgSO , and the solvent was re-
moved in vacuum. 1.05 g of IV could be obtained. H NMR
(
(
ꢀ1
vs), 787 (m), 760 (m), 749 (s), 728 (w), 558 (s), 531 cm (m); ESI-
+
MS (+ve, MeCN): m/z=472.1081 (calcd for [LCu] : 472.1199); ele-
mental analysis calcd (%) for C25
4
ꢀ1
1
H
23CuF
N
6
5
OP (617.99 gmol ): C
4
8.59, H 3.75, N 11.33; found: C 48.69, H 3.77, N 11.60.
(
(
(
400 MHz, CDCl ): d=3.55 (s, 3H, OCH ), 3.62 (s, 3H, Im CH ), 6.45
s, 1H, B-Im CH ), 6.62 (m, 2H, Im CH, 7.03 (m, 1H, B-Im CH), 7.21
3
3
3
OTf
[(L3)Cu]OTf (3 ): The reaction of L3 (100 mg, 0.295 mmol) and
Cu(MeCN) OTf (111 mg, 0.295 mmol) in THF (4 mL) led to the pre-
3
m, 3H, B-Im CH), 7.39 (m, 4H, Ph CH), 7.57 (m, 2H, Py CH-5 and
4
3
CH-3), 7.68 (m, 1H, Ph CH), 8.41 ppm (d, 1H, JH,H =4.0 Hz, Py
CH-6).
cipitation of a white solid, which was isolated by filtration and
OTf
washed with THF (2 mL) and diethyl ether (2 mL). After drying, 3
(
1
148 mg, 0.268 mmol, 91%) was isolated. H NMR (400 MHz,
Ligand L2: Compound IV (1.05 g, 2.7 mmol) and NaH (64 mg,
2
stirred overnight at RT Afterwards MeI (0.17 mL, 2.7 mmol) was
added, and after 3 h the solvent was removed in vacuum. The ob-
tained light brown solid was treated with a mixture of dichlorome-
CD CN): d=1.30 (s, 9H, Pz C(CH ) ), 3.09 (s, 3H, OCH ), 3.23 (s, 3H,
3
3 3
3
.7 mmol) were heated to reflux in THF (15 mL) for 5 h and then
Im NCH ), 3.96 (s, 3H, Pz NCH ), 6.09 (s, 1H, Pz CH-4), 6.89 (s, 1H,
3
3
Im CH-4), 7.07 (s, 1H, Im CH-5), 7.27 (m, 1H, Py CH-5), 7.88 (m, 1H,
3
Py CH-4), 7.99 (d, 1H, JH,H =8.0 Hz, Py CH-3), 8.36 ppm (1H, d,
3
13
JH,H =4.4 Hz, Py CH-6); C NMR (CD CN): d=29.4 (Pz C(CH ) ), 32.0
3
3 3
thane (10 mL) and H O (10 mL). The aqueous layer was extracted
2
(
Pz C(CH ) ), 35.0 (Im NCH ), 39.8 (Pz NCH ), 53.1 (OCH ), 81.8 (C
3 3 3 3 3 q
three times with dichloromethane (5 mL). The combined organic
layers were dried with MgSO4 and the solvent was removed in
vacuum. The oil obtained was purified by column chromatography
with a mixture of acetonitrile, methyl tert-butyl ether, and NEt in
a ratio of 9:3:1. L2 could be isolated in 10% yield (110 mg,
OCH ), 104.8 (Pz CH-4), 121.1 (Py CH-3), 124.0 (Py CH-5), 124.9 (Im
3
CH-5), 127.2 (Im CH-4), 138.4 (Py CH-4), 146.1 (Im C -2), 149.8 (Py
q
CH-6), 150.4 (Pz C -3), 153.9 (Pz C -5), 162.1 ppm (Py CH-2); IR
q
q
3
(
KBr): 3141 (m), 3110 (m), 2965 (m), 2933 (m), 2911 (m), 2880 (w),
2835 (w), 1602 (w), 1570 (w), 1536 (m), 1492 (m), 1476 (m), 1426
m), 1419 (m), 1379 (m), 1369 (m), 1282 (vs), 1259 (vs), 1224 (m),
161 (m), 1141 (s), 1106 (m), 1068 (m), 1049 (m), 1031 (s), 973 (m),
08 (m), 892 (m), 803 (m), 769 (s), 752 (m), 709 (w), 702 (w), 636 (s),
1
0
.27 mmol). H NMR (400 MHz, CDCl ): d=2.92 (s, 3H, OCH ), 3.23
3
3
(
1
9
(
s, 3H, Im CH ), 3.42 (s, 3H, B-Im CH ), 6.85 (s, 1H, Im CH-4), 6.91 (s,
3 3
1
7
1
H, Im CH-5), 7.09 (m, 1H, Py CH-5), 7.24–7.30 (m, 4H, B-Im CH),
.40 (m, 1H, Ph CH), 7.53 (m, 3H, Py CH-4/3 and Ph CH), 7.70 (m,
H, Ph CH), 7.79 (m, 1H, Ph CH), 8.55 ppm (d, 1H, J =2.5 Hz, Py
ꢀ1
3
572 (m), 517 cm (m); ESI-MS (+ve, MeCN): m/z=402.1399 (calcd
for [LCu] : 402.1355); elemental analysis calcd (%) for
C H CuF N O S (552.05 gmol ): C 43.51, H 4.56, N 12.69, S 5.81;
H,H
+
1
3
CH-6); C NMR (400 MHz, CDCl ): d=30.6 (B-Im CH ), 34.8 (Im CH ),
5
CH-5), 123.1 (Im CH-4), 123.3 (Im CH-4), 123.4 (C ), 126.2 (Im CH-5),
1
1
1
3
3
3
ꢀ1
20
25
3
5
4
2.9 (OCH ), 109.0 (C ), 119.3 (Py CH-5), 121.7 (Im CH-5), 122.0 (Py
3 q
found: C 43.60, H 4.41, N 12.67, S 5.59.
q
PF6
27.3 (Ph CH), 128.8 (2C, Ph C ), 129.2 (Ph-Im Cq), 130.2 (Ph CH),
31.8 (Ph C ), 134.9 (2C, B-Im C -4 and B-Im C -9), 135.5 (Py CH-4),
42.2 (B-Im C -2), 146.5 (Im C -2), 148.4 (Py CH-6), 159.4 ppm (Py
[(L3)Cu]PF6 (3 ): The reaction of L3 (136 mg, 0.401 mmol) and
q
Cu(MeCN) PF (149 mg, 0.400 mmol) in THF (4 mL) led to the pre-
q
q
q
4
6
cipitation of a white solid, which was isolated by filtration and
q
q
ꢀ1
PF6
C ); elemental analysis calcd (%) for C H N O (409.48 gmol ): C
washed with THF (2 mL) and diethyl ether (2 mL). After drying, 3
q
25 23
5
7
3.33, H 5.66, N 17.10; found: C 73.29, H 5.82, N 16.12.
(205 mg, 0.374 mmol, 93%) was isolated. Crystals suitable for
Chem. Eur. J. 2015, 21, 1198 – 1207
1205
ꢀ 2015 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim