γ-(6-Methoxy-1, 2, 3, 4-tetrahydro-1-naphthylidene)-butyric acid was prepared according to the method of Stork.This acid could be successfully cyclized to 1-keto-7-methoxy-1, 2, 3, 4, 9, 10-hexahydrophenanthrene by means of 100% orthophosphoric acid at 125-135°.The product obtained gave the characteristic iodine colored 2, 4-dinitrophenylhydrazone, m.p.253-255°.From this ketone, two routes were employed to obtain the desired 1-keto-2-methyl-2-carbomethoxy-7-methoxy-1, 2, 3, 4, 9, 10-hexahydrophenanthrene:(1)1-keto-7-methoxy-1, 2, 3, 4, 9, 10-hexahydrophenanthrene was treated with dimethyl oxalate and sodium methoxide, and methyl 1-keto-7-methoxy-1, 2, 3, 4, 9, 10-hexahydrophenanthrene-2-glyoxalate was obtained in excellent yield as orange prisms, m.p.138-138.5°.