Triethylamine → 6-benzyl-3-methyl-2-thioxo-2,3,5,6,7,8-hexahydropyrido[4,3-d]pyrimidin-4(1H)-one

Participants

Reaction Conditions

Reaction Steps

788 g of methyl 4-amino-1-benzyl-1,2,5,6-tetrahydropyridine-3-carboxylate from a) were dissolved in 2.5 l of toluene, and 447 g of methyl isothiocyanate and 625 ml of triethylamine were added, with stirring. After stirring for 24 h at an internal temperature of 100° C., the mixture was allowed to cool to 20° C. and the precipitate was filtered off with suction and washed with toluene. After drying, this gave 420 g of crude 6 benzyl-3-methyl-2-thioxo-2,3,5,6,7,8-hexahydro-1H-pyrido[4,3-d]pyrimidin-4-one, which was reacted further in c).

Provenance & Evidence