Table 1.
NMR (1H and 13C) chemical and coordination shifts (δ, ppm), alongside multiplicities and coupling constants (JH-H, Hz), for the N-heterocyclic ligands and the corresponding dinuclear platinum(II) complexes 1–3 in D2O as a solvent with TSP as the internal standard.
| Atom position | 1H | 13C | ||
|---|---|---|---|---|
| qx | 1 | qx | 1 | |
| 2,3 | 8.44, s | 9.59, s (+1.15) | 145.67 | 151.77 (+6.10) |
| 5,8 | 7.51, m | 9.73, dd, J = 6.7; 3.3 Hz (+2.22) | 131.94 | 135.93 (+3.99) |
| 6,7 | 7.51, m | 8.41, dd, J = 6.7; 3.3 Hz (+0.90) | 128.83 | 130.09 (+1.26) |
| 4a,8a | — | — | 141.85 | 145.26 (+3.41) |
| qz | 2 | qz | 2 | |
| 2 | 9.09, s | 10.12, d, J = 11.0 Hz (+1.03) | 163.39 | 178.11 (+14.72) |
| 4 | 8.84, s | 9.52, d, J = 8.8 Hz (+0.68) | 156.05 | 168.56 (+12.51) |
| 5 | 7.80, m | 8.51, m | 129.07 | 130.14 (+1.07) |
| 8 | (+0.71) | 131.53 | 132.81 (+1.28) | |
| 6 | 7.79, m | 8.16, m | 130.60 | 135.11 (+4.51) |
| 7 | (+0.37) | 138.42 | 143.10 (+4.68) | |
| 4a | — | — | 126.98 | 128.58 (+1.60) |
| 8a | — | — | 150.76 | 152.39 (+1.63) |
| phtz | 3 | phtz | 3 | |
| 1,4 | 9.18, s | 10.05, s (+0.87) | 154.27 | 164.32 (+10.05) |
| 6,7 | 7.88, m | 8.40, m (+0.52) | 136.61 | 140.50 (+3.89) |
| 5,8 | 7.88, m | 8.40, m (+0.52) | 129.38 | 131.04 (+1.66) |
| 4a,8a | — | — | 129.04 | 130.96 (+1.92) |
The aliphatic methylene protons of the bidentatedly coordinated en ligand in 1–3 give a singlet in the region 2.78–2.84 ppm, while the resonance for the corresponding carbon atoms is in the region 49.42–51.27 ppm. s = singlet; d = doublet; dd = doublet of doublets; m = multiplet.