Boron tribromide → 1,3-Benzenediol, 5-chloro-

Temperature

-78 °C

A solution 5-chloro-1,3-dimethoxybenzene (20.71 g) in dichloromethane (50 ml) at -78° C. was treated dropwise with a solution of boron tribromide (56 ml) in dichloromethane (250 ml), maintaining the temperature at -78° C. The mixture was slowly warmed to room temperature then left at ambient temperature for 48 hours. The reaction mixture was quenched with water (100 ml), (sodium hydroxide scrubber required) and partitioned between water (1000 ml) and dichloromethane (1000 ml). The organic layer was separated and the aqueous layer was extracted twice with a mixture of dichloromethane and methanol (500 ml, 98:2, v/v). The combined organic extracts were washed with saturated brine (200 ml), dried over magnesium sulphate and evaporated affording the title compound (10.17 g) as a yellow/orange oil which was used without further purification.

1. temperatureThe mixture was slowly warmed to room temperature
2. customThe reaction mixture was quenched with water (100 ml), (sodium hydroxide scrubber required)
3. custompartitioned between water (1000 ml) and dichloromethane (1000 ml)
4. customThe organic layer was separated
5. extractionthe aqueous layer was extracted twice with a mixture of dichloromethane and methanol (500 ml, 98:2
6. washThe combined organic extracts were washed with saturated brine (200 ml)
7. dry with materialdried over magnesium sulphate
8. customevaporated

ORD record

ord-34c77e51a979433fb0eaa7629a0f54a6

Source dataset

uspto-grants-2000_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06048893