1,1'-Biphenyl, mixt. with 1,1'-oxybis(benzene) → HCID 12472439, compound

Participants

Reaction Conditions

Reaction Steps

In a 2 liter-4 neck flask fitted with a reflux condenser was placed dimethyl (2E)-2-[(2,4-dioxo-1,2,3,4-tetrahydro-5-pyrimidinyl)amino]-2-butenedioate (Intermediate 1.1) (38.5 g; 0.14 mol; 1 eq.) dowtherm(R) A (1 L)(phenyl ether-biphenyl eutectic). The suspension was stirred with a mechanical stirrer under argon and heated to 220° C. The reaction was monitored by HPLC/LC/MS. After 3 hours the reaction was stopped by cooling followed by the addition of 300 mL of petroleum ether. The resulting precipitate was filtered and washed with DMF (2×100 mL). Methyl 2,4,8-trioxo-1,2,3,4,5,8 hexahydropyrido[3,2-d]pyrimidine-6-carboxylate (21.02 g; 62%) (Intermediate 1.2) was isolated as a yellow powder in 100% HPLC purity.

Provenance & Evidence