Ethyl 3-bromopropionate → 3-{4-[2-(2,5-Dichloro-phenoxy)-5-fluoro-pyridine-3-carbonyl]-3,4-dihydro-2H-quinoxalin-1-yl}-propionic acid ethyl ester

Participants

Reaction Steps

To a solution of [2-(2,5-dichloro-phenoxy)-5-fluoro-pyridin-3-yl]-(3,4-dihydro-2H-quinoxalin-1-yl)-methanone (25.1 mg, 0.06 mmol, 1.0 equiv; Example 147) in anhydrous DMF (1 mL) was added lithium aluminium hydride (2.3 mg, 0.06 mmol, 1.0 equiv; [CAS RN 16853-85-3]) and the reaction mixture stirred at rt. After 30 min, 3-bromo-propionic acid ethyl ester (13.0 mg, 10 μL, 0.072 mmol, 1.2 equiv; [CAS RN 539-74-2]) was added and the reaction mixture heated by microwave irradiation to 150° C. for 30 min. Removal of the solvent mixture under reduced pressure and purification by preparative HPLC on reversed phase (Xterra® PrepMSC 18, 5 μm, 19×50 mm column equipped with a Gilson Liquid Handler 215 autosampler, two Rainin Dynamax® SD-300 pumps, a Sedex ELSD 75 lightscatter and a Dionex UVD 340S UV detector) eluting with a gradient of acetonitrile/water provided 2.4 mg (8%) of the title compound as a light brown oil. MS (ISP): 518.3 [M+H]+.

Provenance & Evidence