Recently we found that 4-methylphenanthrene reacts with acetyl chloride in the Friedel- Crafts reaction in the 1-and 6-positi0ns.~ We have now investigated the reaction between the hydrocarbon and succinic anhydride, and have found that the succinoyl group likewise enters the same positions. From the mixture of keto acids formed in the reaction, p-[3-(5- methylphenanthroyl)]-propionic acid (I)(corresponding to substitution in the 6-position of ...