Reaction #507596

Reaction equation

4-picoline

acetonitrile

1-bromo-2-[(2-bromoethyl)disulphanyl]ethane

N-methylpyrrolidone

→

expected product

Yield 90.0%

1,1′-(disulfanediyldiethane-2,1-diyl)bis(4-methylpyridinium) dibromide

Yield 90.0%

Conditions

Workup

1. 1
   Otherwas brought to 80° C
2. 2
   workup.ADDITIONwas added over 5 min
3. 3
   Temperaturethe mixture was cooled
4. 4
   OtherThe solid obtained
5. 5
   Filtrationwas filtered
6. 6
   Washrinsed with 3×200 ml of acetonitrile
7. 7
   workup.DISSOLUTIONthen dissolved in 800 ml of isopropanol (under reflux)
8. 8
   TemperatureAfter cooling
9. 9
   workup.ADDITION1 l of ethyl ether was added
10. 10
    OtherThe precipitate formed
11. 11
    Filtrationwas filtered
12. 12
    Washrinsed with 3×200 ml of ethyl ether
13. 13
    Otherdried
14. 14
    OtherThe off-white powder obtained (73.77 g)

Procedure

67 g of 4-picoline were diluted in 100 ml of acetonitrile and the mixture was brought to 80° C. A mixture of 60 g of 1-bromo-2-[(2-bromoethyl)disulphanyl]ethane and 15 ml of N-methylpyrrolidone (NMP) was added over 5 min. After stirring for 4 h at 85° C., the mixture was cooled. The solid obtained was filtered, rinsed with 3×200 ml of acetonitrile then dissolved in 800 ml of isopropanol (under reflux). After cooling, 1 l of ethyl ether was added. The precipitate formed was filtered, rinsed with 3×200 ml of ethyl ether, then dried. The off-white powder obtained (73.77 g) very predominantly contained (>90%) the expected product which was used as such for the following step.

Source