Methanesulfonic Acid → HCID 68109080, compound

Participants

Reaction Conditions

Reaction Steps

A mixture of the product of step B (7.0 g, 17.0 mmol) and tert-butyl 4-oxopiperidine-1-carboxylate (3.73 g, 18.7 mmol) was suspended in a mixture of glacial acetic acid (63 mL) and methanesulfonic acid (7 mL). The suspension was heated to 110° C. for 3 h. After cooling to ambient temperature the reaction mixture was concentrated in vacuo, cooled to 0° C., quenched with 5% KOH solution and suspended in 2-propanol (100 mL) followed by addition of di-tert-butyl dicarbonate (4.45 g, 20.4 mmol). After stirring for 12 h, the mixture was concentrated in vacuo and extracted with dichloromethane. The organic layer was concentrated in vacuo and the residue purified by flash column chromatography (SiO2, 95:5 hexanes/ethyl acetate) to give tert-butyl 8-bromo-6-iodo-3,4-dihydrobenzofuro[3,2-c]pyridine-2(1H)-carboxylate (1.0 g, 9%) as a yellow brown solid: 1H NMR (CDCl3, 300 MHz) δ 7.71 (d, J=1.8 Hz, 1H), 7.50 (br s, 1H), 4.49 (br s, 2H), 3.87-3.78 (m, 2H), 2.94-2.87 (m, 2H), 1.50 (s, 9H).

Provenance & Evidence