Potassium Carbonate → rac-tert-butyl 2-((4-(5-(m-tolyl)oxazole-4-carboxamido)-1H-pyrazol-1-yl)methyl)pyrrolidine-1-carboxylate

Participants

Reaction Conditions

Reaction Steps

To N-(1H-pyrazol-4-yl)-5-(m-tolyl)oxazole-4-carboxamide (150 mg, 0.56 mmol) in DMF (1.5 mL), tert-butyl 2-(bromomethyl)pyrrolidine-1-carboxylate (148 mg, 0.56 mmol) was added and K2CO3 (309 mg, 2.24 mmol) followed by tetrabutylammoniumbromide (18 mg, 0.056 mmol). The reaction mixture was heated to 80° C. for 2 h, then tert-butyl 2-(bromomethyl)pyrrolidine-1-carboxylate (1 eq.) followed by heating to 90° C. for 6 h. The reaction mixture was diluted with EtOAc, washed with sat. aq. NaHCO3-solution (1×) and brine (1×). The aq. layers were reextracted with EtOAc (1×). The combined organic layers were dried (MgSO4), filtered and the solvent was removed under reduced pressure. Purification by FC (EtOAc/hex 9:1, Rf=0.45) yielded rac-tert-butyl 2-((4-(5-(m-tolyl)oxazole-4-carboxamido)-1H-pyrazol-1-yl)methyl)pyrrolidine-1-carboxylate as a yellow foam. LC-MS conditions A: tR=0.94 min, [M+H]+=452.23.

Provenance & Evidence