Reaction with phenylmagnesium bromide. A solution of 2.5 g. of III in 10 ml. of benzene was treated with 6 ml. of 2N ethereal phenylmagnesium bromide, giving a deep purple solution and a gummy black precipitate that dissolved when the mixture was kept overnight. Addition of dilute hydrochloric acid, etc. gave 2.9 g. of a pale tan oil that could not be obtained crystalline. This was treated with 10 ml. of 20% methanolic potassium hydroxide, rapid solution occurring, followed by separation of a colorless crystalline potassium salt. This salt was washed with methanol and then ether, then dissolved in water and acidified. The resulting 1,3-diphenyl-l-hydroxyindene-H-carboxylic acid separated as an oil, which crystallized after it had been kept under ether-ligroin for several days. Recrystallization from dilute alcohol gave fine colorless needles, m.p. 163-164°. The compound gave a deep purple color with coned, sulfuric acid Anal. Caled, for C22HAO3: C, 80.5; , 4.91. Found: C, 80.6; H, 4.92. A solution of 0.5 g. of this acid in 5 ml. of acetic acid and 1 ml. of acetyl chloride was treated with 0.5 g. of zinc dust and boiled for 10 min. Water and ether were then added, and the ether solution was extracted with dilute sodium carbonate. This removed 50 mg. of 1,3-diphenylindene-$carboxylic acid, flat yellow needles from dilute acetic acid, m.p. 195-196°that gave no color with coned, sulfuric acid.