メコン酸誘導体の研究 (第8報)

数種のメコン酸関連化合物の0.05N水酸化ナトリウム中の分解について

抄録

Route of decomposition of ethyl comanate (III), chelidonic acid (IV), ethyl O-methylcomenate (VII′), methyl 5, 6-dimethoxycomanate (IX), and dimethyl O-methyl meconate (XI) as a 0.05 m. M solution in 0.05N sodium hydroxide solution at ordinary temperature was clarified through periodical change of their ultraviolet spectra in 0.05N sodium hydroxide solution, their ultraviolet spectrum after leaving them in 0.05N sodium hydroxide solution for a definite length of time and acidification with hydrochloric acid, ultraviolet spectra of several β-diketone compounds in 0.05N sodium hydroxide solution, polarogram of these compounds in 0.1N sodium hydroxide, and coloration reaction of β-diketones to UO^2-, Ti³⁺, and Fe³⁺. It was thereby found that, after ring cleave, (III) underwent decomposition to acetone through the enolate of formylacetone (XXXII), (IV) to acetone through the enolate of oxalylacetone, (VII′) to methoxyacetone through the enolate of ethyl 1-ethoxyoxalyl-3-methoxyacetone (XXIX), (IX) to methoxyacetone through the enolate of methyl 2-methoxyacetoacetate (XXVII), and (XI) to methoxyacetone through the enolate of methyl 1-methoxyoxalyl-3-methoxyacetone (XXX).