L-Proline → HCID 53927006, compound

Participants

Reaction Steps

A solution of 2-6 (28 g, 97.4 mmol), 2-amino-3 formylpyridine (15.5 g, 127 mmol), proline (11.2 g, 97.4 mmol) in ethanol (250 mL) was heated at reflux for 15 h. After cooling and evaporation, the residue was chromatographed (silica gel, 1:1 chloroform/ethyl acetate) to give 2-7 as a yellow oil. TLC Rf =0.41 (silica, 70:25:5 chloroform/ethyl acetate/methanol) 1H NMR (300 MHz, CDCl3) δ 9.09 (m, 1H), 8.14 (m, 2H), 7.43 (m, 2H), 4.17 (q, 2H, 7 Hz), 3.9 (2s, 2H), 3.43 (q, 2H, J=7 Hz), 3.07 (m, 2H), 2.18 (m, 2H), 1.42 (s, 9H), 1.25 (m, 3H).

Provenance & Evidence