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

Participants

Reaction Conditions

Reaction Steps

To [2-(2,5-dichloro-phenoxy)-5-fluoro-pyridin-3-yl]-(3,4-dihydro-2H-quinoxalin-1-yl)-methanone (200 mg, 0.478 mmol, 1.0 equiv; Example 147) was added a 50% solution of glyoxylic acid ethylester in toluene (1.03 g, 1 mL, 1.913 mmol, 4.0 equiv; [CAS RN 924-44-7]), dibutyltin dichloride (14.6 mg, 0.048 mmol, 0.1 equiv; [CAS RN 683-18-1]) and phenylsilane (103.8 mg, 118 μL, 0.956 mmol, 2.0 equiv; [CAS RN 694-53-1]). The reaction mixture was heated by microwave irradiation to 100° 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 82.7 mg (34%) of the title compound as a light yellow solid. MS (ISP): 504.3 [M+H]+.

Provenance & Evidence