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

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To N-acetonyl-8-benzyl-3-(4-isopropoxy-3-methyl-benzoyl)-11-oxa-3,8-diazaspiro[5.5]undecane-10-carboxamide (136 mg, 0.26 mmol) in THF (3 mL) was added Burgess' Salt (155 mg, 0.65 mmol) and the reaction mixture was heated at 75° C. in a sealed vial for 2 hours. The solvents were removed under reduced pressure, and the residue was dissolved in DMF (1 mL), filtered and purified by Waters preparative LC/MS (1-99% ACN/H2O (5 mM HCl)). The desired fractions were concentrated in vacuo and the residue partitioned between EtOAc/saturated aqueous NaHCO3 solution. 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 yield 8-benzyl-10-(5-methyloxazol-2-yl)-11-oxa-3,8-diazaspiro[5.5]undecan-3-yl]-(4-isopropoxy-3-methyl-phenyl)methanone (76 mg, 58%) as a foam. ESI-MS m/z calc. 503.6. Found 504.5 (M+1)+; Retention time: 1.74 minutes (3 min run).

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