Potassium Carbonate → tert-Butyl 4-(2-ethynyl-8-morpholinoimidazo[1,2-a]pyrazin-5-yl)benzoate

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Reaction Steps

To a suspension of compound 81a (239 mg, 0.580 mmol) in anhydrous THF (8 mL) and anhydrous MeOH (3 mL), dimethyl (1-diazo-2-oxopropyl)phosphonate (164 mg, 0.850 mmol) in MeOH (2 mL) was added followed by potassium carbonate (252 mg, 1.82 mmol). The resulting yellow suspension was stirred at rt for 18 h. The mixture was filtered through a pad of diatomaceous earth. The filter cake was washed CH2Cl2. The combined filtrates were concentrated under reduced pressure. The residue was dissolved in DCM and washed with diluted NaHCO3, brine, dried over Na2SO4, filtered, and concentrated under reduced pressure. The residue was purified on preparative TLC (EtOAc/CH2Cl2; 2:3, v/v) to afford compound 81b. Mass Spectrum (LCMS, ESI pos.): Calcd. for C23H25N4O3: 405.2 (M+H). found: 405.4.

Provenance & Evidence