Acetic Acid → HCID 71009034, compound

Temperature

0 °C

A solution of (1S,2S)-rel-2-[(R)-2-ethoxycarbonyl-2,2-difluoro-1-methyl-1-((R)-2-methyl-propane-2-sulfinylamino)-ethyl]-cyclopropanecarboxylic acid tert-butylester (2.23 g, 5.42 mmol) in tetrahydrofuran (20 ml) was treated dropwise under nitrogen at 0° C. with a solution of lithium borohydride (2M in tetrahydrofuran; 5.42 ml, 10.8 mmol), at such a rate that the temperature was kept below 6° C. The orange reaction mixture was stirred at 0° C. for 3 hours. For the workup, acetic acid (654 mg, 623 μl, 10.8 mmol) was added dropwise, keeping the temperature below 10° C., followed by water (0.8 ml). After 70 minutes of stirring, brine and ethyl acetate were added and the mixture was extracted twice with ethyl acetate. The organic layer was washed with brine, dried over sodium sulphate and evaporated. A light green oil was obtained (2.31 g) which was purified by chromatography on silica gel using a gradient of heptane/ethyl acetate=100:0 to 0:100 as the eluent. The (1S,2S)-rel-2-[(R)-2,2-difluoro-3-hydroxy-1-methyl-1-((R)-2-methyl-propane-2-sulfinylamino)-propyl]-cyclopropanecarboxylic acid tert-butyl ester (1.19 g, 59% yield) was obtained as a colorless oil. MS (ISP): m/z=370.1 [M+H]+.

1. customwas kept below 6° C
2. customthe temperature below 10° C.
3. stirringAfter 70 minutes of stirring
4. extractionthe mixture was extracted twice with ethyl acetate
5. washThe organic layer was washed with brine
6. dry with materialdried over sodium sulphate
7. customevaporated
8. customA light green oil was obtained (2.31 g) which
9. customwas purified by chromatography on silica gel using a gradient of heptane/ethyl acetate=100:0 to 0:100 as the eluent

ORD record

ord-8a660767ce31492eb0503d6c8f9a494e

Source dataset

uspto-grants-2014_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08785436B2