Heterocyclic Steroids. Part II: An Unusual Product in the Cyclodehydration of γ ( 7-Methoxy-2-Methyl-2H-Chromene-4) Butyric Acid

Department of Chemistry, Indian Institute of Technology, Madras-36

(Manuscript received 1 August 1972; accepted 10 November 1972)

Attempted cyclodehydration of the bicyclic acid (2a, R = H) under the catalysis of anhydrous ferric chloride in acetic anhydride afforded a most unusual product, 3-acetyl-7-methoxy-2-methyl­chromone instead of the expected tricyclic unsaturated ketone.