Reaction #1960485

Reaction equation

7,8-difluoro-2H-chromene

1,2-difluoro-3-prop-2-ynyloxybenzene

→

7,8-difluorochroman

Solvents

THF

Conditions

Workup

1. 1
   OtherThe batch is evaporated to dryness
2. 2
   Otherthe crude product is purified by column chromatography (SiO2, n-pentane: 1-chlorobutane=4:1)

Procedure

A mixture of 7,8-difluoro-2H-chromene and 1,2-difluoro-3-prop-2-ynyloxybenzene (43.2 g) is hydrogenated at RT for 1 h in 430 ml of THF in the presence of Pd/C (5% of Pd). The batch is evaporated to dryness, and the crude product is purified by column chromatography (SiO2, n-pentane: 1-chlorobutane=4:1), giving pure 7,8-difluorochroman as a pale-yellowish liquid.

Source