Table 3. Further Optimization of Hydrogenolysis Conditions.

| entry | H2 pressure (bar) | Pd/C loading (mol %) | temp (°C) | conversiond (%) |
|---|---|---|---|---|
| 1a | 6 | 7 | 40 | 97 |
| 2b | 4 | 5 | 40 | 98 |
| 3b | 4 | 2.5 | 40 | 99 |
| 4c | 4 | 2.5 | rt | 59 |
Performed on a 63 μmol scale at a concentration of 0.17 M.
Performed on a 127 μmol scale at a concentration of 0.17 M.
Performed on a 0.3 mmol scale at a concentration of 0.1 M.
Conversions were determined by LCMS with reference to caffeine as an internal standard.