反应详情

To a stirred solution of 2,2-dimethyl-3-oxobutyl trifluoroacetate (W. C. Lumma, Jr. and O. H. Ma, J. Org. Chem., 1970, 35, 2391-2393, 8.45 g, 39.8 mmol) in chloroform (26 mL) was added bromine (1.93 mL, 37.8 mmol) in chloroform (14 mL) dropwise at room temperature. The resulting mixture was stirred at room temperature for 1 h. The mixture was poured into crashed ice/water, and aqueous Na2S2O3 (20 mL) and aqueous NaH2PO4 (40 mL) were added. After the mixture was extracted with chloroform (3×30 mL), the extract was dried over magnesium sulfate and concentrated. Distillation of the residue at 99-102° C. under diminished pressure (3.4 mmHg) afforded 3.58 g (30%) of the title compound as colorless oil.

1. additionThe mixture was poured
2. additionwere added
3. extractionAfter the mixture was extracted with chloroform (3×30 mL)
4. dry with materialthe extract was dried over magnesium sulfate
5. concentrationconcentrated
6. distillationDistillation of the residue at 99-102° C. under diminished pressure (3.4 mmHg)