Methyl 3-oxovalerate → 5-ethyl-2-mercapto-3H-pyrano[2,3-d]pyrimidine-4,7-dione

Participants

Reaction Steps

A mixture of 4,6-dihydroxy-2-mercapto-pyrimidine (20.0 g, 138.7 mmol) and methyl propionylacetate (21.8 mL, 173.4 mmol) was heated at 165° C. until the ester was completely reacted. The reaction mixture was cooled down and poured into water (75 mL) and then filtered through a sintered funnel. The solid residue was washed with water (2×20 mL) and dried under vacuum to yield 5-ethyl-2-thioxo-2,3-dihydro-1h-pyrano[2,3-d]pyrimidine-4,7-dione (11.6 g, 37%).

Provenance & Evidence