Bromine → 5'-Bromo-2,6-dichloro-4'-methoxy-2'-methyl-benzophenone

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

A solution of bromine (0.25 ml in 3 ml of trichloromethane) is added dropwise to a stirred solution of 2,6-Dichloro-4'-methoxy-2'-methyl-benzophenone (1.5 g; 5 mmol in 5 ml of trichloromethane), followed by 15 minutes of stirring at 20° C. The mixture is shaken with water, sodium hydrogencarbonate solution and water. The organic phase is dried and evaporated. The residue is purified by chromatography (flash column filled with 30 g of silicagel, elution with petrolether/ethylacetate changing from 20:1 to 9:1, 8:2, 7:3 (v/v) . After evaporation, the residue crystallises when treated with petrolether/toluene to give white crystalls (0.45 g; 24% y); mp. 159° C.

Herkunft & Nachweise