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

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

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.

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