0.57 g of succinic anhydride was added to a solution of 1.79 g of 3-dimethylamino-1-[2-(4-phenylbutyl)phenoxy]-2-propanol [prepared as described in Example 1(b)] in 50 ml of acetone, and the resulting mixture was heated under reflux for 2 hours. At the end of this time, the reaction mixture was cooled, and 1.5 ml of a 4N solution of hydrogen chloride in dioxane were added, and the mixture was allowed to stand at room temperature. The crystals which precipitated were collected by filtration and dried in vacuo, to give 2.20 g (yield 93%) of the title compound as colorless crystals, melting at 123°-125° C.
