Reactions of 14‐hydroxy‐14‐azadispiro[5.1.5.2]pentadec‐9‐ene‐7,15‐dione and related compounds. II

Abstract 3 When 11‐diethyl‐ and 3, 11‐di‐ n ‐propyl‐14‐hydroxy‐14‐azadispiro[5.1. 5.2]pentadec‐9‐ene‐7, 15‐dione (E‐IV and n ‐Pr‐IV) are heated with polyphosphoric acid at 55–65°, the 14‐hydroxyl group cyclizes at the 11‐carbon to form E‐VI and n ‐Pr‐VI, the structures of which have been established. Compounds P‐IV, i ‐Pr‐IV and t ‐B‐IV do not cyclize under these conditions. The Beckmann rearrangement of 12‐hydroxy‐12‐azadispiro[4.1.4.2]tridec‐8‐ene‐6, 13‐dione‐6‐oxime (P‐I) with polyphosphoric acid at 40–50° formed only the normal product, P‐II, which could not be cyclized. Compound P‐IV was the only ketone of this series which would add hydrogen cyanide to form a cyanohydrin.