Aluminum chloride (1.13 g, 8.46 mmol) was added to a solution of 2-methoxy-6-methylsulfonylnaphthalene (1.0 g, 4.2 mmol) [prepared as described in example 2 above], and 4-fluorobenzenesulfonyl chloride (1.65 g, 8.46 mmol) in 1,2 dichloroethane (40 ml). The reaction mixture was heated at reflux for 16 h, and then poured into 2N HCl and extracted into methylene chloride. The organic layer was separated, washed with water and brine, and dried over sodium sulfate. Purification by flash chromatography gave 0.1 g of 5-(4-fluoro-phenylsulfonyl)-6-methoxy-2-methylsulfonylnaphthalene as a solid (16% yield).
