4-Toluenesulfonyl chloride → (R)-5-bromo-3-(1-methyl-2-pyrrolidinylmethyl)-1-tosyl-1H-indole

Participants

Reaction Steps

To a stirred solution of (R)-5-bromo-3-(1-methyl-2-pyrrolidinylmethyl)-1H-indole (10.0 g, 34.1 mmol) in ethyleneglycol dimethylether (50 ml) at 0° C. under a nitrogen atmosphere was added potassium hydroxide flake (9.58 g, 171 mmol) in one portion. Para-toluenesulfonyl chloride (6.83 g, 35.8 mmol) was then added portionwise to the brown slurry over a 5 min period, maintaining the temperature below 5° C. The brown slurry was then warmed to ambient temperature and stirred for a further 2 hr. The mixture was then filtered in vacuo and the filter cake washed with toluene (2×100 ml). The filtrate was then concentrated in vacuo to approximately 20 ml volume which resulted in precipitation of a cream solid. After stirring for 2 hr, the solid was filtered and dried in vacuo at 50° C. for 12 hr to give the title compound (9.91 g, 65%) as a beige solid. m.p. 98-104° C.

Provenance & Evidence