Reaction of Biguanides and Related Compounds. XIII. Benzilic Acid Rearrangement. The Reactions of 1, 2-Cyclohexanedione and 9, 10-Phenanthrenequinone with Arylbiguanides and N-Amidino-0-alkylisoureas

Abstract

Benzilic acid rearrangements of 1, 2-cyclohexanedione (I) and 9, 10-phenanthrenequinone (II) are described : The base-catalysed condensation of I with arylbiguanides (III) and with N-amidino-O-alkylisoureas (IV) gave 2-arylguanidylidene-4-oxo-1, 3-diazaspiro [4. 4] nonanes (V) and 2-alkoxyamidinylidene-4-oxo-1, 3-diazaspiro [4. 4] nonanes (X) respectively. Analogously, the reaction of II with III and with IV afforded 2-arylguanidylidene-5-fluorenylidene-4-oxoimidazolidines (XI) and 2-alkoxyamidinylidene-5-fluorenylidene-4-oxoimidazolidines (XII) respectively.