4-Methylmorpholine → N-[(1,1-Dimethylethoxy)carbonyl]-D-alanine 2,5-dioxo-1-pyrrolidinyl ester
Reaction equation
CN1CC[O:5][CH2:4][CH2:3]1.ClC(O[CH2:12][CH:13]([CH3:15])[CH3:14])=O.C([CH2:23][C@H:24]([NH2:28])[C:25]([OH:27])=[O:26])C[C@@H](N)C(O)=O.NC[C:31]([OH:33])=[O:32].C[Si]([CH:38]([Si](C)(C)C)[C:39]([NH2:41])=[O:40])(C)C>ClCCl.CN(C)C=O>[NH:28]([C:31]([O:33][C:13]([CH3:12])([CH3:14])[CH3:15])=[O:32])[C@@H:24]([C:25]([O:27][N:41]1[C:4](=[O:5])[CH2:3][CH2:38][C:39]1=[O:40])=[O:26])[CH3:23]Participants
Reactant 4
Product 1
Reagents, catalysts & solvents 2
Conditions
- Temperature
- -40 °C
Procedure
To a mixture of Compound (1) (674 mg.) and N-methylmorpholine (202 mg.) in dichloromethane (30 ml.), there was added isobutyl chloroformate (273 mg.) at -15°--20° C. and the mixture was stirred for 30 minutes at the same temperaure. The mixture was cooled to -40° C., and to this, there was added trimethyl silyl ester of Compound (2), which was prepared from Compound (2) (910 mg.) and bis(trimethylsilyl)acetamide (3 ml.) by stirring in a mixture of dichloromethane (20 ml.) and N,N-dimethylformamide (2 ml.). This mixture was stirred for 1 hour at -15°--20° C., and after evaporation of the solvent, the residue was dissolved in ethylacetate (100 ml.), and then the solution was washed successively with 2%--HCl and water, dried over MgSO4 and evaporated. The residue was pulverized with isopyropyl ether to give Compound (3) (1.25 g.).
Workup
- stirringThis mixture was stirred for 1 hour at -15°--20° C.
- customafter evaporation of the solvent
- dissolutionthe residue was dissolved in ethylacetate (100 ml.)
- washthe solution was washed successively with 2%
- dry with materialHCl and water, dried over MgSO4
- customevaporated
Sources & evidence
- ORD record
- ord-881113d111af496980c5da4e72a9ff35
- Source dataset
- uspto-grants-1985_09
- Patent number
- US04539155
Reaction notes
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