Reaction #2507824

Reaction equation

3,5-difluorosalicylaldehyde

p-methoxyphenol

DABCO

→

6,8-difluoro-2H-chromene-3-carbonitrile

Solvents

acrylonitrile

Conditions

Workup

1. 1
   OtherThe batch is evaporated
2. 2
   Filtrationthe solution is filtered through silica gel

Procedure

84 g (0.531 mol) of 3,5-difluorosalicylaldehyde are dissolved in 850 ml of acrylonitrile, 1 g (8 mmol) of p-methoxyphenol and 18 g (0.16 mol) of DABCO are added, and the mixture is heated overnight at 75° C. The batch is evaporated, the residue is taken up in dichloromethane, and the solution is filtered through silica gel, giving 6,8-difluoro-2H-chromene-3-carbonitrile, which is sufficiently pure for further reactions.

Source