Reaction #1106680

Reaction equation

hydrochloric acid

Catechol

sodium methoxide

methyl dichloroacetate

→

benzo[1,3]dioxole-2-carboxylic acid methyl ester

Solvents

Water

methanol

Conditions

Workup

1. 1
   TemperatureThe solution was heated
2. 2
   Temperatureto reflux overnight
3. 3
   Extractionthe mixture was extracted with diethyl ether (3×100 mL)
4. 4
   DryingThe combined organic solution was dried with MgSO4
5. 5
   Concentrationconcentrated to a brown solid
6. 6
   Otherchromatographed (2% ethyl acetate in hexane)

Procedure

Catechol (10.26 g, 93.2 mmol), sodium methoxide (25% by weight in methanol, 40.3 g, 186 mmol), and methyl dichloroacetate (13.3 g, 93.2 mmol) were combined in dry methanol (100 mL). The solution was heated to reflux overnight. The reaction was cooled to room temperature, acidified by addition of concentrated hydrochloric acid and then reduced in volume under vacuum to about 50 mL. Water was added and the mixture was extracted with diethyl ether (3×100 mL). The combined organic solution was dried with MgSO4, concentrated to a brown solid, and chromatographed (2% ethyl acetate in hexane) to yield benzo[1,3]dioxole-2-carboxylic acid methyl ester as a colorless oil.

Source