Methane → Naratriptan Hydrochloride

Participants

Reaction Steps

A mixture of (E)-N-methyl-2-[3-(1,2,3,6-tetrahydro-1-methyl-4-pyridinyl)-1H-indol-5-yl]ethenesulphonamide hydrochloride (500 g) and 10% palladium oxide on charcoal (50% wet paste, 700g added as three charges) in DMF (3L), water (3L) and methanol (1.5L) was hydrogenated at atmospheric pressure over 24 hr. The suspension was filtered and the filter cake washed with water (500 mL). The filtrate was concentrated to approximately 2L by distillation in vacuo. Ethyl acetate (5L) was added over 10 mins and the mixture cooled to 5°. The product was filtered off, washed with ethyl acetate (1L) and dried in vacuo at 45° overnight (453 g, 90.1% of theory). Recrystallisation from hot water (1.36L) afforded white crystals (324.0 g, 71.2% of theory).

Provenance & Evidence