Thionyl Chloride → 2-Chloronicotinoyl chloride

Participants

Reaction Steps

Thionyl chloride (2.48 ml, 10 eq) and DMF (2 drops) were added to a solution of 2-chloronicotinic acid (535 mg, 3.4 mmol) in dichloromethane (3 ml). The mixture was heated at reflux overnight then concentrated in vacuo and azeotroped with toluene (2×5 ml) to give 2-chloronicotinoyl chloride as a yellow oil. A solution of this acid chloride in dichloromethane (5 ml) was added dropwise to a solution of Intermediate 5 (750 mg, 2.69 mmol) and NMM (355 μl, 1.2 eq) in dichloromethane (15 ml) at 00. Dimethylaminopyridine (catalytic) was added and the mixture stirred at room temperature for 2 h. The mixture was then concentrated in vacuo. The residue was dissolved in ethyl acetate (50 ml) and washed with aqueous NaHCO3 (2×50 ml). The organic phase was dried (MgSO4) and concentrated in vacuo, to give the title compound. δH (CDCl3) 10.55 (1H, s), 8.51 (1H, m), 8.05 (1H, m), 7.67 (1H, m), 7.57 (3H, m), 7.2 (2H, m), 4.24 (1H, m), 3.62 (3H, s), 3.08 (2H, m), 1.03 (9H, s); m/z (ESI, 70V) 418 (M++H).

Provenance & Evidence