17.4 g (51 mmol) of 2-methyl-4,8-diphenyl-3,5,6,7-tetrahydro-s-indacen-1(2H)-one (4b) and 3.8 g (100 mmol) of sodium borohydride in 100 ml of toluene were placed in a reaction vessel. The solution was heated to 50° C. and 22 ml of methanol was slowly added and the reaction mixture was stirred at 50° C. for 3 hours and then at room temperature overnight. During stirring solids were precipitated. 12 ml of water and 80 ml of 1 N sulfuric acid were added and the mixture was stirred at 35° C. for 30 minutes. 200 ml of methylene chloride was added and organic phase was separated and evaporated and the residue (18.0 g) was taken up in 200 ml of toluene and mixed with 100 mg of p-toluenesulfonic acid. Water was distilled off from this reaction mixture by refluxing for 1 hour on a water separator until reaction was complete. The reaction mixture was washed once with 100 ml of saturated sodium hydrogen carbonate solution and dried over magnesium sulfate. After removal of the solvent, the residue was dried in an oil pump vacuum. This gave 18 g of pale brawn solid. The crude product was purified by column chromatography.
