反应详情

A stirred solution of 3,4-dichlorophenylmagnesium bromide [prepared from 3,4-dichlorobromobenzene (10.2 g, 45 mmol) and magnesium (1.1 g, 45 mmol) in the usual fashion] was treated with a solution of 3-chloro-1,4-oxathiane [prepared from 1,4-oxathiane (2.6 g, 25 mmol) using the method of Tuleen and Bennet J. Het. Chem. 1969, 6, 115] in benzene (30 ml), maintaining the temperature of reaction below 10° C. The mixture was allowed to stand at room temperature overnight. It was then poured into ammonium chloride solution (50 ml), the organic phase was separated and the aqueous washed with ether (2×40 ml). The combined organic extracts were dried (MgSO4) and purified by flash chromatography on silica eluting with toluene/hexane (1:1) to give 3-(3,4-dichlorophenyl)-1,4-oxathiane (4.5 g), as colourless crystals, m.p. 65°-68° C.;

1. customthe temperature of reaction below 10° C
2. customthe organic phase was separated
3. washthe aqueous washed with ether (2×40 ml)
4. dry with materialThe combined organic extracts were dried (MgSO4)
5. custompurified by flash chromatography on silica eluting with toluene/hexane (1:1)