Benzenesulfonic acid, 4-methyl-, compd. with pyridine (1:1) → Methyl ((8R)-8-{[(4-fluorophenyl)sulfonyl](methyl)amino}-8,9-dihydro-pyrido[3,2-b]indolizin-5-yl)acetate

Participants

Reaction Steps

To a mixture of methyl [1-((2R)-2-{[(4-fluorophenyl)sulfonyl](methyl)amino}-4-oxobutyl)-1H-pyrrolo[2,3-b]pyridin-3-yl]acetate (272 g, 589 mmol) in ethyl acetate (2.5 L) was added PPTS (326.33 g, 1299 mmol). After a period of 4 days at 65° C., the reaction mixture was quenched with saturated sodium bicarbonate and extracted with ethyl acetate. The organic phase was separated, washed with brine, dried over sodium sulfate, filtered and evaporated under reduced pressure. The residue was purified by combiflash (10% ethyl acetate in hexane to 100% ethyl acetate) to give the title compound.

Provenance & Evidence