Reaction #969845

ord-d0633b1a8d424c299d1fbced2d978c76

Reaction equation

O=C(O)Cc1cccs1
thiolacetic acid
CCN(C(C)C)C(C)C
DIPEA
C1CCOC1
THF
COC(=O)C(Br)CCBr
methyl 2,4-dibromobutanoate
C1CCOC1
THF
COC(=O)C(CCBr)SC(C)=O
title compound
Yield 96.0%
COC(=O)C(CCBr)SC(C)=O
Methyl 2-(acetylthio)-4-bromobutanoate
Yield 96.0%

Conditions

Temperature
-20°CELSIUS
Detailed conditions
See reaction.notes.procedure_details.

Workup

  1. 1
    workup.WAIT0° C. for 2 hours under Ar
  2. 2
    Concentrationthe mixture was concentrated
  3. 3
    workup.ADDITIONdiluted with EtAc/Hexane
  4. 4
    Washwashed with 1.0 M NaH2PO4
  5. 5
    Dryingdried over MgSO4
  6. 6
    Filtrationfiltered
  7. 7
    Otherevaporated
  8. 8
    OtherSiO2 chromatographic purification (1:12 to 1:10 EtAc/Hexane)

Procedure

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)

Source

DOI: 10.6084/m9.figshare.5104873.v1Patent: US08236319B2uspto-grants-2012_08