Methanesulfonic Acid → N-Methyl-3-(((2R)-1-methyl-2-pyrrolidinyl)methyl)-1H-indole-5-methanesulfonamide

Participants

Reaction Steps

A mixture of (R)-N-Benzyloxymethyl-1-[1-benzyloxymethyl-3-(1-methyl-2-pyrrolidinylmethyl)-1H-indol-5-yl]-N-methylmethanesulfonamide (from step (f), 300 mg, 0.5 mmol) and methanesulfonic acid (60 mg, 0.6 mmol) in water (5 ml) was hydrogenated over Pearlman's catalyst (300 mg) at 60° C. and at 345 kPa (50 psi) for 18 hr. The solution was then filtered through a pad of celite (trade mark) and the filtrate was partitioned between saturated sodium bicarbonate (25 ml) and dichloromethane (3×50 ml). The combined organic extract was then evaporated in vacuo and the residue was dissolved in a mixture of THF and water (1:1) (10 ml). A solution of Triton B (40% w.w. in methanol) (0.2 ml, 0.44 mmol) was then added dropwise and the solution was then refluxed for 2 hr. The solution was then cooled to ambient temperature before being poured into water (10 ml) and extracted with dichloromethane (3×25 ml). The combined organic extracts were evaporated in vacuo to give a yellow film. This was then triturated with IMS (5 ml) and tie solid was filtered in vacuo and dried at 50° C. overnight to yield the title compound (50 mg, 29%) as a white solid. m.p. 209-231° C.

Provenance & Evidence