Ammonium Chloride → 4-Bromo-7-methyl-6,7-dihydro-5H-cyclopenta[C]pyridin-7-OL

Participants

Reaction Conditions

Reaction Steps

A brown suspension of 4-bromo-5H-cyclopenta[c]pyridin-7(6H)-one (intermediate A-4[B]) (424 mg, 2.0 mmol) in THF (5 mL) was cooled (−78° C.) and treated during 10 min with methylmagnesium bromide (2.1 mL, 3.0 mmol, 1.4 M in THF:toluene 1:3). The reaction was allowed to warm up to RT over 3 h then stirred for 1.5 h at RT. The mixture was poured on aq. sat. NH4Cl-solution and extracted with EtOAc (3×). The organic layer was dried over Na2SO4 and concentrated in vacuo. Purification by flash chromatography (50 g SiO2, Telos-cartridge, CH2Cl2/MeOH (4%)) gave the title compound (180 mg, 40%) as dark green viscous oil. MS: 228.0 (M+H+, 1Br).

Provenance & Evidence