Triethylamine → tert-butyl (2S,4E)-4-methoxyimino-2-(2-oxo-3H-1,3,4-oxadiazol-5-yl)pyrrolidine-1-carboxylate
Reaction equation
[NH:1]([C:3]([C@@H:5]1[CH2:9][C:8](=[N:10][O:11][CH3:12])[CH2:7][N:6]1[C:13]([O:15][C:16]([CH3:19])([CH3:18])[CH3:17])=[O:14])=[O:4])[NH2:2].C(N(CC)CC)C.[C:27](N1C=CN=C1)(N1C=CN=C1)=[O:28]>C1COCC1>[CH3:12][O:11]/[N:10]=[C:8]1\[CH2:9][C@@H:5]([C:3]2[O:4][C:27](=[O:28])[NH:2][N:1]=2)[N:6]([C:13]([O:15][C:16]([CH3:19])([CH3:18])[CH3:17])=[O:14])[CH2:7]\1Participants
Reactant 3
Product 1
Reagents, catalysts & solvents 1
Procedure
To a stirring solution of tert-butyl (2S,4EZ)-2-(hydrazinocarbonyl)-4-(methoxyimino)-1-pyrrolidinecarboxylate (Intermediate 9, 1.84 mmoles; 500 mg) and triethylamine (2.76 mmoles; 27 mg) in THF (25 mL) at 0° C. was added 1,1′-carbonyldiimidazole (2.76 mmoles, 448 mg). The stirring was continued for 5 hours. Another portion of triethylamine and 1,1′-carbonyldiimidazole were added and stirring was continued at room temperature overnight. The solvent was evaporated and the residue was dissolved in EtOAc and washed with NH4Clsat., and 10% NaHCO3, and brine. The organic layer was dried over Na2SO4 and evaporated to dryness to give the desired N-protected intermediate, tert-butyl (2S,4E)-4-(methoxyimino)-2-(5-oxo-4,5-dihydro-1,3,4-oxadiazol-2-yl)-1-pyrrolidinecarboxylate, as a white foam (460 mg, 84%).
Workup
- waitwas continued at room temperature overnight
- customThe solvent was evaporated
- dissolutionthe residue was dissolved in EtOAc
- washwashed with NH4Clsat
- dry with materialThe organic layer was dried over Na2SO4
- customevaporated to dryness
Sources & evidence
- ORD record
- ord-5155c31358f042c99086b354f891d03c
- Source dataset
- uspto-grants-2006_10
- Patent number
- US07115639B2
Reaction notes
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