Methanesulfonic Acid → Eletriptan

Participants

Reaction Steps

A stirred solution of (R)-5-(2-benzenesulfonylethenyl)-3-(N-methylpyrrolidin-2-ylmethyl)-1H-indole (34.0 g) in acetone (200 mL) was treated with methanesulfonic acid (8.5871 g) then 5% palladium on carbon (50% wet) (34.0 g) added and the mixture exposed to hydrogen (50 psi) at ambient temperature. When conversion was judged to be complete the mixture was filtered (washing with acetone--85 mL--and mixed acetone/water--81 mL/4 mL). The combined filtrate and washings were diluted with water (800 mL) and the pH adjusted (with stirring) to about 11 by addition of 40% aqueous sodium hydroxide. After granulation of the precipitate the solids were collected by filtration to give the title compound (25.08 g) as that produced in Example 32).

Provenance & Evidence