(2-Oxopropyl)amine → N-acetonyl-8-benzyl-3-(4-isopropoxy-3-methyl-benzoyl)-11-oxa-3,8-diazaspiro[5.5]undecane-10-carboxamide

Participants

Reaction Conditions

Reaction Steps

To 8-benzyl-3-(4-isopropoxy-3-methyl-benzoyl)-11-oxa-3,8-diazaspiro[5.5]undecane-10-carboxylic acid (201 mg, 0.43 mmol), 1-aminopropan-2-one (47 mg, 0.43 mmol) and T3P (641 μL of 50% w/w, 1.08 mmol) was added 2-methyltetrahydrofuran (1 mL) and the reaction mixture was then 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 20-70% EtOAC in DCM as eluent to afford N-acetonyl-8-benzyl-3-(4-isopropoxy-3-methyl-benzoyl)-11-oxa-3,8-diazaspiro[5.5]undecane-10-carboxamide (92 mg, 41%) as a yellow solid. ESI-MS m/z calc. 521.6. found 522.5 (M+1)+; Retention time: 1.48 minutes (3 min run).

Provenance & Evidence