Oxalyl chloride → (2S)-2-((1,1-Dimethylethyl)dimethylsilyloxy)propanoyl chloride
Reaction equation
[CH3:1][C:2]([Si:5]([CH3:20])([CH3:19])[O:6][C@@H:7]([CH3:18])[C:8](O[Si](C(C)(C)C)(C)C)=[O:9])([CH3:4])[CH3:3].C(Cl)(=O)C([Cl:24])=O>CN(C)C=O.C(Cl)Cl>[CH3:1][C:2]([Si:5]([CH3:20])([CH3:19])[O:6][C@@H:7]([CH3:18])[C:8]([Cl:24])=[O:9])([CH3:4])[CH3:3]Participants
Reactant 2
Product 1
Reagents, catalysts & solvents 2
Procedure
To a solution of 41.0 g (0.13 mol) of 2-(1,1-dimethylethyl)dimethylsilyl (2S)-2-((1,1-dimethylethyl)dimethylsilyloxy)propanoate (7) and five drops of N,N-dimethylformamide in methylene chloride at 0° C. was added 70.8 mL (0.14 mol) of a 2.0M solution of oxalyl chloride in methylene chloride over a 30 minute period. The cooling bath was removed and the reaction mixture was allowed to stir at room temperature for 18 hours. The solvent and excess oxalyl chloride were removed by rotary evaporation resulting in a yellow liquid. Purification by vacuum distillation afforded 25.6 g (88%) of (2S)-2-((1,1 -dimethylethyl)dimethylsilyloxy)propanoyl chloride (8) as a clear liquid: bp 42°-45° C. (1.5 mm Hg); 1H NMR (CDCl3) δ0.0920 (s, 3 H), 0.118 (s, 3 H), 0.909 (s, 9 H), 1.50 (d, J=6.7 Hz, 3 H), 4.49 (q, J=6.7 Hz, 1 H); 13C NMR (CDCl3) δ176.6, 76.0, 25.7, 25.6, 25.3, 20.9, 18.1, -1.57, -5.04, -5.28.
Workup
- customThe cooling bath was removed
- customThe solvent and excess oxalyl chloride were removed by rotary evaporation
- customresulting in a yellow liquid
- customPurification
- distillationby vacuum distillation
Sources & evidence
- ORD record
- ord-f60824d0d7ad4036b85f4d51636dac67
- Source dataset
- uspto-grants-1993_05
- Patent number
- US05208345
Reaction notes
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