Dimethyl acetylenedicarboxylate → HCID 136502909, compound

Participants

Reaction Conditions

Reaction Steps

N-[(1Z)-1-amino-1-(hydroxyimino)-2-methylpropan-2-yl]-5-methyl-1,3,4-oxadiazole-2-carboxamide (IVa) (198 gms) was suspended in methanol (1188 ml) and cooled to 15 to 25° C. Dimethyl acetylenedicarboxylate (DMAD; 152.8 gms) was added and the reaction mass was stirred for 2 to 3 hours at 25° C. The reaction mass was concentrated under reduced pressure and xylene was added and stirred between 135° C. and 125° C. for 6 hour. After completion of reaction, the mixture was cooled to 60° C. and methanol (170 ml) & methyl tert-butyl ether (MTBE) were added to the reaction mass and stirred for 1 hour. The resultant slurry was filtered and washed with a 9:1 mixture of methanol & methyl tert-butyl ether (MTBE) and dried to give methyl 2-(2-(5-methyl-1,3,4-oxadiazole-2-carboxamido)propan-2-yl)-1,6-dihydro-5-hydroxy-6-oxopyrimidine-4-carboxylate (Va).

Provenance & Evidence