反应详情

A mixture of 4-2 (540 mg, 1.4 mmol), 2-amino-3-formylpyridine (170 mg, 1.4 mmol; for prep. see JOC 1983,48, 3401) and proline (161 mg, 1.4 mmol) in absolute ethanol (20 mL) was heated at reflux for 12 h. Following evaporative removal of the solvent, the residue was chromatographed (silica gel, 50% ethyl acetate/chloroform 70:25:5 chloroform/ethyl acetate/MeOH) to give 4-3 as a yellow oil.

1. temperaturewas heated
2. temperatureat reflux for 12 h
3. customremoval of the solvent
4. customthe residue was chromatographed (silica gel, 50% ethyl acetate/chloroform 70:25:5 chloroform/ethyl acetate/MeOH)