Methyl 5-chloropyrazine-2-carboxylate → 5-Chloropyrazinoic acid

Temperature

160 °C

To a solution of methyl-5-chloropyrazine-2-carboxylate (120 mg, 0.70 mmol) in a mixture of acetonitrile (2 mL) and DMF (1 mL) was added lithium chloride (295 mg, 6.95 mmol). The suspension was heated to 160° C. for 5 minutes in a microwave after which time the reaction was diluted with water (10 mL). Saturated sodium bicarbonate solution (20 mL) was added and the aqueous layered extracted with ethyl acetate (2×30 mL). The organic extracts were discarded and the aqueous layer adjusted to pH 4 with 1N hydrochloric acid. The aqueous phase was extracted twice with ethyl acetate (20 mL) and the combined organics washed with water (2×20 mL) and brine (10 mL) and dried (MgSO4). The volatiles were removed under reduced pressure to afford the product (68 mg). 1H NMR δ (400 MHZ, CDCl3): 7.20 (1H, br s), 8.72 (1H, s), 9.21-9.21 (1H, m); m/z 157 (M−H)+.

1. extractionthe aqueous layered extracted with ethyl acetate (2×30 mL)
2. extractionThe aqueous phase was extracted twice with ethyl acetate (20 mL)
3. washthe combined organics washed with water (2×20 mL) and brine (10 mL)
4. dry with materialdried (MgSO4)
5. customThe volatiles were removed under reduced pressure

ORD record

ord-d903815d55db4075b857b04ae9d89a82

Source dataset

uspto-grants-2011_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07902200B2