Hydrochloric Acid → (3R)-3-tert-Butoxy-1-chlorobutan-2-one

A mixture of 8.00 g (50 mmol) of methyl (R)-2-(tert-butyloxy)propionate, 8.74 g (75 mmol) of sodium chloroacetate, 7.53 g (75 mmol) of triethylamine, and 200 mL of THF was cooled in ice, and 93.8 g (150 mmol) of a 1.6 M solution of tert-butylmagnesium chloride was added dropwise thereto over a period of 2 hours. After the completion of the dropwise addition, the reaction was performed at room temperature for another 2 hours, the reaction solution was cooled in ice again. Then, 20 mL of concentrated hydrochloric acid was added thereto, and subsequently 100 mL of ethyl acetate was added. Stirring was performed at room temperature for 1 hour. Then, the resulting organic layer was separated, dried over anhydrous sodium sulfate, and concentrated under reduced pressure to obtain 7.35 g of a crude product. The resulting product was purified by column on silica gel to obtain 6.66 g of the title compound (yield: 80%). 1H-NMR (400 MHz, CDCl3) δ: 1.21 (s, 9H), 1.35 (d, 3H, J=6.6 Hz), 4.20 (q, 1H, J=6.6 Hz), 5.50 (s, 2H).

1. temperaturewas cooled in ice
2. additionAfter the completion of the dropwise addition
3. waitthe reaction was performed at room temperature for another 2 hours
4. temperaturethe reaction solution was cooled in ice again
5. waitwas performed at room temperature for 1 hour
6. customThen, the resulting organic layer was separated
7. dry with materialdried over anhydrous sodium sulfate
8. concentrationconcentrated under reduced pressure
9. customto obtain 7.35 g of a crude product
10. customThe resulting product was purified by column on silica gel

ORD record

ord-4f33a4d29ec74b048c8bae9c97ec6e19

Source dataset

uspto-grants-2009_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07582781B2