Diisopropylethylamine → [2-Chloro-4-(2,5-dichloro-phenoxy)-6-methyl-pyridin-3-yl]-(4-cyclopropyl-3,4-dihydro-2H-quinoxalin-1-yl)-methanone

Participants

Reaction Steps

To a solution of 120 mg (0.355 mmol) lithium 2-chloro-4-(2,5-dichloro-phenoxy)-6-methyl-nicotinate in 3 mL dry N,N-dimethylformamide was added 0.30 mL (1.773 mmol) N-ethyldiisopropylamine and 163 mg (0.425 mmol) 0-(7-azabenzotriazol-1-yl)-N,N,N′,N′-tetramethyluronium hexafluorophosphate (HATU, commercially available, CAS RN 148893-10-1) and 74 mg (0.425 mmol) 1-cyclopropyl-1,2,3,4-tetrahydro-quinoxaline (Example 8, intermediate a). The reaction mixture was stirred for 18 hours at room temperature and evaporated. The residue was purified on a preparative HPLC system (Phenomenex Gemini column) using a gradient of acetonitrile:water (containing 0.05% formic acid) (50:50 to 100:0) to provide 45 mg (26%) of the title compound as a light yellow foam (30%). MS (ESI): m/z=488.07 [M+H]+.

Provenance & Evidence