The Acid-catalyzed Decomposition of α-Diazo β-Hydroxy Ketones

Article abstract of DOI:10.1246/bcsj.54.2142

The proton acid-catalyzed decomposition of 3-aryl-2-diazo-3-hydroxy-1-phenylpropanone (1) gave aryl and hydrogen migration products.The former was the enol-form (2) of 2-aryl-3-phenyl-1,3-propanedione and the latter was the enol- (3) and keto-form (4) of 1-aryl-3-phenyl-1,3-propanedione.The product ratios, 2/(3+4), were affected by the catalysts and solvents used.More polar solvents favored the formation of aryl migration products (2).On the other hand, the BF3-catalyzed decomposition of 1 gave acetylenic ketones as main products along with 2, 3, 4.The TsOH-catalyzed decomposition of 2-diazo-3-hydroxy-3-phenyl-1-indanone, (cyclic α-diazo β-hydroxy ketone), gave 2-phenyl-1,3-indandione quantitatively through phenyl migration.