1-(3-Chloro-4-fluorobenzyl)-5,6-dihydropyridin-2(1H)-one → Ethyl 6-(3-chloro-4-fluorobenzyl)-4-hydroxy-5-oxo-5,6,7,8-tetrahydro-2,6-naphthyridine-1-carboxylate

Participants

Reaction Conditions

Reaction Steps

A mixture of ethyl 5-butoxy-1,3-oxazole-2-carboxylate (248 g, 1.16 mol; Example 1, step 5), 1-(3-chloro-4-fluorobenzyl)-5,6-dihydropyridin-2(1H)-one (199.2 g, 0.83 mol; Example 1, step 2), and deionized water (22.5 mL, 1.25 mol) in a glass lined stainless steel high pressure reactor (with the interstitial space between the liner and the pressure vessel was filled with water) was heated at 135° C. with stirring for 72 hours. The product mixture was cooled in an ice-water bath and the gaseous by-product was carefully vented. The orange solid product was triturated with methyl tert-butyl ether (300 mL) and collected by filtration. The product recrystallized from boiling ethanol-water (˜500 mL, 9:1 v/v), collected by filtration, washed successively with a small quantity of ethanol, methyl tert-butyl ether (300 mL), and heptane (200 mL), and air dried to afford the title compound.

Provenance & Evidence