Hydrochloric Acid → 4-[4-(1-benzofuran-5-yl)phenyl]-5-{[1-(cyclopropylcarbonyl)-3-azetidinyl]methyl}-2,4-dihydro-3H-1,2,4-triazol-3-one

Participants

Reaction Conditions

Reaction Steps

In a microwave vial purged with nitrogen, a mixture of 4-(4-bromophenyl)-5-{[1-(cyclopropylcarbonyl)-3-azetidinyl]methyl}-2,4-dihydro-3H-1,2,4-triazol-3-one (83 mg, 0.220 mmol), 1,1′-bis(diphenylphosphino)ferrocene-palladium(II)dichloride dichloromethane complex (9 mg, 11 μmol), and 5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1-benzofuran (59 mg, 0.242 mmol) in 1,4-dioxane (2 mL) and 2M aq potassium carbonate (0.5 mL, 1.00 mmol) was stirred at 100° C. in an oil bath for 22 h. Additional 5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1-benzofuran (59 mg, 0.242 mmol) and 1,1′-bis(diphenylphosphino)ferrocene-palladium(II)dichloride dichloromethane complex (9 mg, 11 μmol) were added and the reaction mixture was heated at 100° C. in an oil bath for 20 h. The reaction was cooled to room temperature, poured into water (50 mL), and adjusted to pH˜4.5 with 1N aq HCl. The aqueous layer was extracted with ethyl acetate (3×50 mL). The combined organic layers were dried over sodium sulfate, filtered, and concentrated in vacuo. Purification of the residue by flash chromatography (ethyl acetate, then 0-10% methanol/ethyl acetate) followed by a second purification by reverse phase HPLC (20-70% acetonitrile/water+0.1% NH4OH) provided the title compound as an ivory solid (37 mg, 38%). MS(ES)+ m/e 415.2 [M+H]+.

Provenance & Evidence