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yield of 86 % (248 mg, 0.6 mmol). C14H10Cl2N4Pd (411.58): calcd. C 40.85,
Synthesis of Chlorido-(4′-R-2,2′:6′,2′′-terpyridine)palladium Chlor-
H 2.47, N 13.6; found C 40.84, H 2.41, N 13.54. 1H NMR ([D6]DMSO, ide, [(R′terpy)PdCl]Cl. General Procedure: [(COD)PdCl2] (100 mg,
300 MHz): δ = 10.19 (s, 1 H, 6-H), 9.25 (d, J = 5.5 Hz, 1 H, 6′-H), 8.78 (d, 0.35 mmol) was dissolved in CH2Cl2 (20 mL) and a solution of the li-
J = 7.8 Hz, 1 H, 3′-H), 8.61 (d, J = 8.7 Hz, 2 H, 2′′/6′′-H), 8.48 (t, J = 8.4 Hz,
1 H, 4′-H), 8.04 (t, J = 6.6 Hz, 1 H, 4′′-H), 7.83 (t, J = 7.3 Hz, 1 H, 5′-H),
7.73 (t, J = 7.5 Hz, 2 H, 3′′/5′′-H) ppm. EI-MS (70 eV, 320 °C): m/z = 376
gands L7 or L8 (0.35 mmol) in CH2Cl2 (10 mL) was slowly added. The
mixture was stirred at ambient temperature overnight, and the resulting
precipitate was filtered off, washed with small portions of diethyl ether
[M – HCl]+, 339 [M – HCl2]+, 234 [L1]+. UV/Vis (DMF): λmax = 283, 336 nm. and n-pentane and dried under reduced pressure. [(terpy)PdCl]Cl was
obtained as a yellow microcrystalline material. Yield: 94 % (135 mg,
[(L2)PdCl2]: Orange dichlorido-[5-(3′′-methoxyphenyl)-3-(2′-pyridyl)-
0.33 mmol). C15H11Cl2N3Pd (410.59): calcd. C 43.88, H 2.70, N 10.23;
1,2,4-triazine]palladium [(PyTZ3MeOPh)PdCl2] was obtained from L2
found C 43.78, H 2.72, N 10.24. 1H NMR ([D6]DMSO, 300 MHz): δ = 8.77
(92.5 mg, 0.35 mmol), with a yield of 91 % (141 mg, 0.32 mmol).
(d, 2 H, 6/6′′-H), 8.67 (d, 2 H, 3/3′′-H), 8.63 (m, 3 H, 3′/4′/5′-H), 8.48 (dd,
C15H12Cl2N4OPd (441.61): calcd. C 40.80, H 2.74, N 12.69; found C 40.86,
2 H, 4/4′′-H), 7.90 (dd, 2 H, 5/5′′-H) ppm (compare with ref.[91]). EI-MS
1
H 2.70, N 12.67. H NMR ([D6]DMSO, 300 MHz): δ = 10.20 (s, 1 H, 6-H),
(70 eV, 302 °C): m/z = 375 [M – HCl]+, 338 [M – HCl – Cl]+, 233 [terpy]+.
9.25 (d, J = 8.7 Hz, 1 H, 6′-H), 8.80 (d, J = 11.7 Hz, 1 H, 3′-H), 8.48 (t, 1
H, 4′-H), 8.19 (d, 1 H, 6′′-H), 8.10 (s, 1 H, 2′′-H), 8.05 (t, J = 8.5 Hz, 1 H,
5′-H), 7.65 (t, J = 8.2, 2.3 Hz, 1 H, 5′′-H), 7.65 (d, J = 8.0 Hz, 1 H, 4′′-H),
3.94 (s, 3 H, OCH3) ppm. EI-MS (70 eV, 305 °C): m/z = 406 [M – HCl]+,
264 [L2]+. UV/Vis (DMF): λmax = 302, 336, 370 nm.
[(4-MeS-terpy)PdCl]Cl was obtained as a yellow/off-white micro-
crystalline material. Yield: 86 % (137 mg, 0.3 mmol). C16H13Cl2N3PdS
(456.68): calcd. C 42.08, H 2.87, N 9.20, S 7.02; found C 42.18, H 2.92, N
9.24, S 7.04. 1H NMR ([D6]DMSO, 300 MHz): δ = 8.66 (d, J = 7.9 Hz, 2 H,
6/6′′-H), 8.50 (d, J = 5.4 Hz, 2 H, 3/3′′-H), 8.42 (t, J = 7.8 Hz, 2 H, 4/4′′-
H), 8.32 (s, 2 H, 3/5-H), 7.82 (t, 2 H, 5/5′′-H), 2.79 (s, 3 H, SCH3) ppm
(compare with ref.[92]). EI-MS (70 eV, 275 °C): m/z = 375 [M – Cl – SCH3]+,
338 [M – SCH3 – 2Cl]+, 279 [MeSterpy]+, 233 [terpy]+.
[(L3)PdCl2]: Orange dichlorido-[5-(4′′-methoxyphenyl)-3-(2′-pyridyl)-
1,2,4-triazine]palladium [(PyTZ4MeOPh)PdCl2] was obtained from L3
(92.5 mg, 0.35 mmol), with a yield of 89 % (137 mg, 0.31 mmol).
C15H12Cl2N4OPd (441.61): calcd. C 40.80, H 2.74, N 12.69; found C 40.82,
1
H 2.76, N 12.71. H NMR ([D6]DMSO, 300 MHz): δ = 10.07 (s, 1 H, 6-H),
[6-(phen-2-id)-2,2′-bipyridine]chloridopalladium(II) [(Phbpy)PdCl]
9.21 (d, 1 H, 6′-H), 8.76 (d, 1 H, 3′-H), 8.61 (d, J = 9.0 Hz, 2 H, 2′′/6′′-H),
8.47 (t, J = 7.8, 1.5 Hz, 1 H, 4′-H), 8.02 (t, 1 H, 5′-H), 7.25 (d, J = 12.0 Hz,
2 H, 3′′/5′′-H), 3.95 (s, 3 H, OCH3) ppm. EI-MS (70 eV, 315 °C): m/z = 406
[M – HCl]+, 264 [L3]+. UV/Vis (DMF): λmax = 287, 387 nm.
K2[PdCl4] (131.4 mg, 0.4 mmol) was dissolved in water (10 mL) and a
solution of 6-phenyl-2,2′-bipyridine (HPhbpy, 93.5 mg) in MeCN (10 mL)
was added; the resulting orange solution was heated under reflux for
20 h. After cooling, the resulting yellow precipitate was filtered off,
washed with water and n-hexane (20 mL portions) and dried in vacuo.
Yield: 78 % (116.5 mg, 0.31 mmol). Constable et al. report a yield of
86 % under these conditions.[9]
[(L4)PdCl2]: Yellow dichlorido-[5-(4′′-trifluoromethylphenyl)-3-(2′-pyr-
idyl)-1,2,4-triazine]palladium [(PyTZ4CF3Ph)PdCl2] was obtained from L4
(53 mg, 0.165 mmol), with a yield of 91 % (72 mg, 0.15 mmol).
C15H9Cl2F3N4Pd (479.58): calcd. C 37.57, H 1.89, N 11.68; found C 37.52,
1
H 1.86, N 11.71. H NMR ([D6]DMSO, 300 MHz): δ = 10.29 (s, 1 H, 6-H),
Alternatively, 6-phenyl-2,2′-bipyridine (81 mg, 0.35 mmol) and
[(COD)PdCl2] (100 mg, 0.35 mmol) were dissolved in dry MeCN (20 mL).
After stirring the reaction mixture at ambient temperature for about
12 h, a yellow material precipitated. This material was filtered off and
washed with MeCN (5 mL). The 1H NMR spectrum of this material
showed signals of the cyclometalated product [(Phbpy)PdCl] and the
uncoordinated ligand HPhbpy in a 3:1 ratio, pointing to an incomplete
reaction. Importantly, no further signals were detected, for example, for
the assumed dichlorido complex [(HPhbpy)PdCl2]. After a reaction time
of about 3 d at ambient temperature, the reaction was complete, yield-
ing 91 % (120 mg, 0.32 mmol) of pure [(Phbpy)PdCl]. C16H11ClN2Pd
(373.14): calcd. C 51.50, H 2.97, N 7.51; found C 51.48, H 2.92, N 7.54. 1H
NMR ([D6]DMSO, 300 MHz): δ = 8.66 (d, 1 H, 6′-H), 8.52 (d, 1 H, 3′-H),
8.27 (dd, 1 H, 4′-H), 8.24 (d, 1 H, 3-H), 8.18 (dd, 1 H, 4-H), 8.03 (d, 1 H,
5-H), 7.80 (ddd, 1 H, 5′-H), 7.68–7.63 (m, 1 H, 3′′-H), 7.57–7.51 (m, 1 H,
6′′-H), 7.15–7.05 (m, 2 H, 4′′H5′′-H) ppm. 13C{1H} NMR ([D6]DMSO,
300 MHz): δ = 163.5, 155.1, 154.0, 153.5, 149.0, 148.0, 140.4, 140.1, 136.1,
129.6, 127.4, 124.7, 124.6, 123.1, 119.9, 119.8 ppm. EI-MS: (20 eV, 175 °C):
m/z = 374 [M]+, 462 [ligand–ligand]+, 337 [M – Cl]+, 231 [Phbpy]+.
9.26 (d, J = 6.5 Hz, 1 H, 6′-H), 8.81 (d, J = 8.0 Hz, 3 H, 3′/2′′/6′′-H), 8.51
(t, 1 H, 4′-H), 8.12–8.03 (m, 3 H, 3′′/5′′/5′-H) ppm. EI-MS (70 eV, 285 °C):
m/z = 444 [M – HCl]+, 302 [L4]+. UV/Vis (DMF): λmax = 335, 364, 391 nm.
[(L5)PdCl2]: Yellow dichlorido[5-(4′′-fluorophenyl)-3-(2′-pyridyl)-1,2,4-tri-
azine]palladium [(PyTZ4FPh)PdCl2] was obtained from L5 (180 mg,
0.7 mmol), with a yield of 94 % (287 mg, 0.67 mmol). C14H9Cl2FN4Pd
(429.57): calcd. C 39.14, H 2.11, N 13.04; found C 39.12, H 2.09, N 13.01.
1H NMR ([D6]DMSO, 300 MHz): δ = 10.17 (s, 1 H, 6-H), 9.25 (d, J = 5.5 Hz,
1 H, 6′-H), 8.80 (d, 1 H, 3′-H), 8.72 (dd, J = 9.0 and 5.4 Hz, 2 H, 2′′/6′′-H),
8.48 (td, J = 7.8 and 1.4 Hz, 1 H, 4′-H), 8.04 (ddd, J = 7.5, 5.7 and 1.5 Hz,
1 H, 5′-H), 7.60 (d, J = 8.8 Hz, 2 H, 3′′/5′′-H) ppm. EI-MS (70 eV, 300 °C):
m/z = 394 [M – HCl]+, 252 [L5]+. UV/Vis (DMF): λmax = 303, 335, 364 nm.
[(L6)PdCl2]: [(COD)PdCl2] (200 mg, 0.7 mmol) was dissolved in acetone
(25 mL) and a solution of L6 (218 mg, 0.7 mmol) dissolved in acetone
(25 mL) was slowly added. The initial yellow colour intensified and after
about 5 min, a yellow precipitate was observed. After stirring for 60 min,
the solid product was collected in a filter, washed with small portions
of diethyl ether and n-pentane and dried under reduced pressure. Thus,
we obtained a yellow microcrystalline powder, with a yield of 81 %
Chlorido(mesityl)(2,2′-bipyridine)palladium(II)
[(bpy)Pd(Mes)Cl]:
(276.5 mg, 0.56 mmol). C18H12Cl2N6Pd (489.65): calcd. C 44.15, H 2.47, [(PPh3)2Pd(Mes)Cl] (320 mg, 0.41 mmol) and bpy (70 mg, 0.45 mmol)
N 17.16; found C 43.92, H 2.44, N 17.14. 1H NMR ([D6]DMSO, 600 MHz):
δ = 9.28 (d, J = 5.4 Hz, 1 H, 6′-H), 8.68 (d, J = 7.7 Hz, 1 H, 3′-H), 8.48 (m,
2 H, 4′/6′′-H), 8.44 (m, 1 H, H-6′′′), 8.40 (m, 1 H, 6′′-H), 8.33 (d, J = 7.8 Hz,
1 H, 3′′′-H), 8.10–8.04 (m, 4 H, 5′/3′′/4′′/4′′′-H), 7.55 (m, 1 H, 5′′′-H), 7.51
were dissolved in THF (200 mL) and stirred at 60 °C overnight. The
volume was reduced to 10 mL, upon which, a yellow product precipi-
tated. Filtration and recrystallisation from CH2Cl2/n-heptane and drying
in vacuo gave a yield of 67 % (118 mg, 0.28 mmol). Alternatively,
(m, 1 H, 5′′-H) ppm. 13C NMR ([D6]DMSO, 151 MHz): δ = 163.4 (C3), [(COD)Pd(Mes)Cl] (370 mg, 1 mmol) and bpy (172 mg, 1.1 mmol) were
156.7 (C6), 154.8 (C5), 152.3 (C2′′), 152.1 (C2′′′), 150.9 (C2′), 149.7 (C6′), dissolved in toluene (100 mL) and heated to 70 °C for 3 d. The yellow
148.9 (C6′′′), 148.7 (C6′′), 141.5 (C4′), 137.3 (C4′′/4′′′), 129.7 (C5′), 126.6 solution was carefully separated from a black precipitate, the toluene
(C3′), 125.9 (C5′′′), 125.0 (C3′′′), 124.7 (C5′′), 124.0 (C3′′) ppm. 15N NMR
was distilled off and the yellow residue was recrystallised from CH2Cl2/
([D6]DMSO, 60.83 MHz): δ = 318.7 (N′′′), 316.7 (N′′), 219.7 ppm. (N′)- n-heptane several times. Yield: 69 % (288 mg, 0.69 mmol). C19H19ClN2Pd
triazine N atoms were not detected. EI-MS (70 eV, 272 °C): m/z = 454
(417.24): calcd. C 54.70, H 4.59, N 6.71; found C 54.65, H 4.51, N 6.70. 1H
NMR (CDCl3, 300 MHz): δ = 9.43 (d, 1 H, 6-H); 8.02 (d, 1 H, 3-H); 7.99 (m,
[M – HCl]+, 312 [L6]+. UV/Vis (DMF): λmax = 366, 304 nm.
Eur. J. Inorg. Chem. 2017, 2011–2022
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