4 9 10 diaceanthanthrene is obtained the yield is 98 5 greenish brown prisms from dioxane the product does not melt till 360 u00b0 c the identity of the product with that obtained by the procedure described in a is confirmed by the coincidence of their respective ir spectra l 1 0 g of 5 5 39 diacenaphthenyl 6 6 39 diacetyl and 2 0 g of koh are boiled in 20 ml of pyridine for 30 minutes the reaction mass is poured onto 100 ml of water the precipitate is filtered off washed with water and dried 0 9 g of the product is obtained which is treated with boiling dioxane and the portion soluble in the boiling dioxane is separated the weight of the crystalline product isolated from the dioxane is 0 8 g the yield is 88 the identity of the product thus obtained with that prepared in a is confirmed by the coincidence of their respective ir spectra a 1 0 g of 5 5 39 diacenaphthenyl 6 6 39 dipropionyl is heated in a mixture of 60 ml of acetic acid and 10 ml of hydrobromic acid at a temperature of 70 u00b0 c during 2 hours the dark green precipitate is filtered off washed with a small quantity of acetic acid then with water and dried 0 5 g of the product is obtained the yield being 50 the product is recrystallized from a benzene petroleum ether mixture the product does not melt till 250 u00b0 c b 2 0 g of 5 5 39 diacenaphthenyl 6 6 39 dipropionyl and 4 0 g of zinc dust are heated in a mixture of 75 ml of acetic acid and 10 ml of a 4 solution of hcl in.