1,2-Dibromoethane → 6-Methyl-2,3-dihydro-1,4-benzodioxine

Participants

Reaction Conditions

Reaction Steps

A mixture of 4-methylcatechol (33.04 g, 266.1 mmol), 1,2-dibromoethane (100 g, 532.3 mmol), K2CO3 (75.4 g, 545.5 mmol) and sodium iodide (0.2 g, 1.33 mmol) in ethylene glycol (500 mL) was heated to 130° C. under nitrogen for five hours. The solution was allowed to cool to ambient temperature and stirred overnight. After the mixture was filtered through celite, the solution was diluted with brine (800 mL) and extracted with organic solvents (CH2Cl2/hexane/EtOAc: 1:3:1,3×500 mL). The organic layer was dried over Na2SO4, filtered and concentrated to provide a crude oil. Flash silica gel chromatography eluting with hexane (100%) gradient to ether/hexane (8:2) afforded the title intermediate as a colorless oil 20.0 g (50%).

Provenance & Evidence