Acetyl chloride → 6-Acetyl-5,6,7,8-tetrahydro-1,6-naphthyridine

Participants

Reaction Steps

To a solution of 5,6,7,8-tetrahydro-1,6-naphthyridine (4.9 g, 36.5 mmol) in CH2Cl2 at 0° C. was added triethylamine (6.1 ml, 43.8 mmol) and acetyl chloride (3.11 ml, 43.8 mmol) dropwise and the reaction was allowed to warm to room temperature and stirred for a further 18 h. The reaction mixture was partitioned between H2O and CH2Cl2, the layers were separated and the aqueous layer was extracted twice more with CH2Cl2. The combined organic layers were dried over MgSO4 and evaporated under reduced pressure to afford a residue which was purified on silica gel, eluting with EtOAc/MeOH/0.88NH3 (95/5/1, v/v). This afforded the subtitle compound (58%) as an oil. Rf 0.60 (CH2Cl2/MeOH/0.88NH3 84/14/2, v/v). 1H NMR (CDCl3) δ: 2.15 (3H, s), 3.04 (2H, m), 3.75 and 3.90 (2H,2×m), 4.60 and 4.70 (2H,2×s), 7.10 (1H, m), 7.42 (1H,m), 8.42 (1H, m).

Provenance & Evidence