Table 2. Effect of Acidic Additives and Temperature on the Ratio of Byproducts in the Hydrogenation of PPNa.
| composition
of byproduct |
|||||||
|---|---|---|---|---|---|---|---|
| no. | acidic additive/substrate ratio (mol mol–1) | temperature (°C) | PPN (%) | TPPA (%) | BPPA (%) | PPAL (%) | PPOH (%) |
| 1 | 2.0 NaH2PO4 | 30 | 85.2 | 14.8 | 0 | 0 | 0 |
| 50 | 71.5 | 28.5 | 0 | 0 | 0 | ||
| 80 | 55.0 | 45.0 | 0 | 0 | 0 | ||
| 2 | 1.0 NaH2PO4/1.0 H2SO4 | 30 | 73.0 | 20.1 | 0 | 6.9 | 0 |
| 50 | 53.6 | 41.4 | 0 | 3.5 | 1.5 | ||
| 80 | 31.1 | 66.5 | 0 | 0.8 | 1.6 | ||
| 3 | 2.0 NaH2PO4/2.0 H2SO4 | 80 | 33.5 | 62.7 | 0 | 1.2 | 2.6 |
a
Conditions: 5.0 g (38.2 mmol) PPN, 1.5 g 10% Pd/C (Selcat Q) catalyst, 250 mL water and 50 mL dichloromethane, 6 bar, reaction time: 7 h.