Tetrahydrofuran → Methyl 2-(acetylthio)-4-bromobutanoate

Temperature

-20 °C

10.0 g (38.4 mmol) of methyl 2,4-dibromobutanoate in 100 ml of dry THF at −20° C. was added dropwise the mixture of 2.75 ml (38.5 mmol) of thiolacetic acid in 8.5 ml (48.9 mmol) of DIPEA and 50 ml of dry THF in 1.5 hour. After stirring overnight at −20° C. then 0° C. for 2 hours under Ar, the mixture was concentrated, diluted with EtAc/Hexane, washed with 1.0 M NaH2PO4, dried over MgSO4, filtered, evaporated, and SiO2 chromatographic purification (1:12 to 1:10 EtAc/Hexane) to afford 9.5 g (96%) of the title compound. 1H NMR (CDCl3) 4.38 (1H, t, J=7.1 Hz), 3.74 (s, 3H), 3.40 (m, 2H), 2.57˜2.47 (m, 1H), 2.37 (s, 3H), 2.36˜2.21 (m, 1H); 13C NMR 193.24, 171.36, 53.15, 44.45, 34.67, 30.46, 29.46; MS m/z+ 276.9 (M+Na), 278.9 (M+2+Na)

1. wait0° C. for 2 hours under Ar
2. concentrationthe mixture was concentrated
3. additiondiluted with EtAc/Hexane
4. washwashed with 1.0 M NaH2PO4
5. dry with materialdried over MgSO4
6. filtrationfiltered
7. customevaporated
8. customSiO2 chromatographic purification (1:12 to 1:10 EtAc/Hexane)

ORD record

ord-329271028afd45ea8f8cd28b4f717d6a

Source dataset

uspto-grants-2013_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08613930B2