Reaction #1914824

Reaction equation

16-bromohexadecanoic acid

HCl

sodium

NaOH

thiolacetic acid

→

desired product

Yield 97.2%

16-Mercaptohexadecanoic acid

Yield 97.2%

Solvents

methanol

Conditions

Workup

1. 1
   workup.ADDITIONAt the end of the addition reaction mixture
2. 2
   workup.STIRRINGAfter additional 10 min of stirring
3. 3
   workup.ADDITIONwere added
4. 4
   TemperatureThe resulted mixture was refluxed for 15 hrs
5. 5
   Temperatureto cool to RT
6. 6
   TemperatureAdditional refluxing for 3 hrs
7. 7
   Otherrequired for reaction completion
8. 8
   OtherResulted
9. 9
   Otherreaction mixture
10. 10
    Temperaturewas cooled with ice bath
11. 11
    workup.ADDITIONpoured
12. 12
    workup.STIRRINGwith stirring, into a vessel
13. 13
    Extractionextracted with 300 ml of ether
14. 14
    OtherThe organic layer was separated
15. 15
    Washwashed with 3×150 ml of water, 150 ml of saturated NaCl aqueous solution
16. 16
    Dryingdried over sodium sulfate
17. 17
    OtherAfter removal of ether material
18. 18
    Otherwas purified by recrystalization from n-hexane
19. 19
    Filtrationfiltering out
20. 20
    Otherdrying over high vacuum

Procedure

Under inert atmosphere 2.0 gr of sodium metal suspension (40% in mineral oil) were slowly added to 100 ml of dry methanol at 0° C. At the end of the addition reaction mixture was stirred for 10 min at RT and 1.75 ml (21.58 mmole) of thiolacetic acid were added. After additional 10 min of stirring, 30 ml degassed methanolic solution of 6.1 gr (18.19 mmole) of 16-bromohexadecanoic acid were added. The resulted mixture was refluxed for 15 hrs, after which, allowed to cool to RT and 50 ml of degassed 1.0 M NaOH aqueous solution were injected. Additional refluxing for 3 hrs required for reaction completion. Resulted reaction mixture was cooled with ice bath and poured, with stirring, into a vessel containing 200 ml of ice water. This mixture was titrated to pH=7 by 1.0 M HCl and extracted with 300 ml of ether. The organic layer was separated, washed with 3×150 ml of water, 150 ml of saturated NaCl aqueous solution and dried over sodium sulfate. After removal of ether material was purified by recrystalization from n-hexane, filtering out and drying over high vacuum. 5.1 gr (97% yield) of the desired product were obtained.

Source