Reaction #83826

Reaction equation

3-fluoro-pyrid-2-ylsulfonamide

2-fluoroethanol

sodium hydride

→

title product

3-(2-fluoroethoxy)-pyrid-2-ylsulfonamide

Solvents

tetrahydrofuran

tetrahydrofuran

Conditions

Workup

1. 1
   Otherdoes not exceed 20° C
2. 2
   workup.ADDITIONWhen the dropwise addition
3. 3
   workup.STIRRINGThe reaction solution is then stirred for 10 minutes at room temperature and for 2 hours
4. 4
   Temperatureat reflux before it
5. 5
   Temperatureis cooled
6. 6
   Concentrationconcentrated
7. 7
   OtherFor purification
8. 8
   Otherthe oil remaining is chromatographed on a silica gel column
9. 9
   OtherEvaporation of the eluant
10. 10
    Otheryields a light-coloured oil which
11. 11
    Othercrystallises spontaneously

Procedure

5.76 ml of 2-fluoroethanol are added dropwise, with cooling, to a suspension of 6.54 g of sodium hydride (55.6% NaH in oil) in 120 ml of tetrahydrofuran so that the temperature does not exceed 20° C. When the dropwise addition is complete, the reaction mixture is stirred at room temperature for 15 minutes and then a further solution of 10.56 g of 3-fluoro-pyrid-2-ylsulfonamide in 60 ml of tetrahydrofuran is added dropwise over a period of 10 minutes. The reaction solution is then stirred for 10 minutes at room temperature and for 2 hours at reflux before it is cooled and concentrated. For purification, the oil remaining is chromatographed on a silica gel column using ethyl acetate/hexane 4/1. Evaporation of the eluant yields a light-coloured oil which crystallises spontaneously, yielding 5.88 g of title product which melts at 122°-123° C.

Source