Triethyl Phosphate → Allyl 4-[4-cyano-2-(phenylsulfonyl)phenyl]-6-methyl-2-oxo-1-[3-(trifluoromethyl)phenyl]-1,2,3,4-tetrahydropyrimidine-5-carboxylate

Participants

Reaction Conditions

Reaction Steps

The reaction was carried out under argon. Triethyl phosphate (172 mg, 0.947 mmol) and diphosphorus pentoxide (90 mg) were stirred at 40° C. overnight. The mixture was then diluted with MTBE (9.5 ml), and 4-formyl-3-(phenylsulfonyl)benzonitrile (214 mg, 0.789 mmol), 1-[3-(trifluoromethyl)phenyl]urea (0.161 g, 0.789 mmol) and allyl acetoacetate (0.168 g, 1.18 mmol; 1.5 eq.) were added. The mixture was stirred under reflux for 16 h. The reaction mixture was then concentrated by distillative removal of MTBE and subsequently heated at 90° C. for a further 2 h. For work-up, residual solvent was removed under reduced pressure and the residue was taken up in ethyl acetate (150 ml). The organic phase was washed with saturated sodium chloride solution (2×30 ml), dried over solid sodium sulfate, filtered and concentrated under reduced pressure. The crude product was purified by preparative HPLC (column: Gromsil C-18; mobile phase: acetonitrile/water+0.1% TFA 10:90→90:10). The title compound was obtained as a solid (230 mg, 33% of theory).

Provenance & Evidence