Triethylamine → [8-Benzyl-10-(3-methyl-1,2,4-oxadiazol-5-yl)-11-oxa-3,8-diazaspiro[5.5]undecan-3-yl]-(4-isopropoxy-3-methyl-phenyl)methanone

Participants

Reaction Conditions

Reaction Steps

T3P (546 mg, 510 μL of 50% w/w, 0.86 mmol) was added to a solution of 8-benzyl-3-(4-isopropoxy-3-methyl-benzoyl)-11-oxa-3,8-diazaspiro[5.5]undecane-10-carboxylic acid (160 mg, 0.34 mmol), N′-hydroxyacetamidine (25 mg, 0.34 mmol) and triethylamine (173 mg, 239 μL, 1.71 mmol) in 2-methyltetrahydrofuran (800 μL) and the reaction mixture was heated at 75° C. for 2 hours. The reaction mixture was cooled to room temperature and partitioned between EtOAc/saturated aq. NaHCO3. The layers were separated and the aqueous layer was extracted with EtOAc (2×). The combined organics were dried over Na2SO4, filtered and concentrated in vacuo to a dark foam. The crude product was purified by silica gel column chromatography using 0-30% EtOAc in DCM as eluent to afford [8-benzyl-10-(3-methyl-1,2,4-oxadiazol-5-yl)-11-oxa-3,8-diazaspiro[5.5]undecan-3-yl]-(4-isopropoxy-3-methyl-phenyl)methanone (67 mg, 39%) as a white solid. ESI-MS m/z calc. 504.6. Found 505.3 (M+1)+; Retention time: 1.63 minutes (3 min run).

Provenance & Evidence