Pyridine → Ethyl n-[(5-bromothien-2-yl)sulfonyl]-4,4,4,4',4',4'-hexafluoro-DL-valinate

Temperature

25 °C

A solution of ethyl 4,4,4,4′,4′,4′-hexafluoro-dl-valinate (1.64 g, 6.48 mmol), prepared as described (J. Med Chem 1981, 24, 1043–1047), in CH2Cl2 (10 mL) was stirred under N2 atmosphere at 25° C. Pyridine (0.81 mL, 10.04 mmol) was added dropwise followed by 5-bromothiophene-2-sulfonyl chloride (2.034 g, 7.77 mmol) in one portion and the resulting solution stirred for 19 h at 25° C. After this time period, the reaction was complete by TLC (1:4 EtOAc-hexane). After quenching with water (2.0 mL), the mixture was diluted with CH2Cl2 (40 mL). The organic layer was washed sequentially with 1N aqueous HCl (20 mL), saturated aqueous NaHCO3 (20 mL) and brine (15 mL), dried over MgSO4, filtered, and concentrated to obtain a crude oil (3.3 g). The crude product was purified by the Biotage Flash™ 40 chromatography system, eluent: 1:6 EtOAc-hexanes, to afford ethyl N-[(5-bromothien-2-yl)sulfonyl]-4,4,4,4′,4′,4′-hexafluoro-dl-valinate as a white solid (2.40 g, 80.0%). Mass Spectrum (−ESI): 477 (M−H)−.

1. customAfter quenching with water (2.0 mL)
2. additionthe mixture was diluted with CH2Cl2 (40 mL)
3. washThe organic layer was washed sequentially with 1N aqueous HCl (20 mL), saturated aqueous NaHCO3 (20 mL) and brine (15 mL)
4. dry with materialdried over MgSO4
5. filtrationfiltered
6. concentrationconcentrated
7. customto obtain a crude oil (3.3 g)
8. customThe crude product was purified by the Biotage Flash™ 40 chromatography system, eluent

ORD record

ord-83f39e3fe35c4d00aeeb6e890f001b01

Source dataset

uspto-grants-2007_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07300951B2