高級脂肪酸と金属ナトリウムとの反応 (第4報)

高級脂肪酸エステルより誘導されるアシロインおよびα-ジケトンについて

抄録

The Series of acyloins were prepared from C₆C₁₆ saturated fatty acid methyl esters by means of the method studied by V.L. Hansley. These acyloins were quantitatively oxidized with Wijs solution to give the corresponding α-diketones. The properties of these acyloins and α-diketones were discussed in this study.
The melting point of each α-diketone is higher than that of the corresponding acyloin. The hydroxyl group of acyloins can be quantitatively acetylated by the acetic anhydride, and carbonyl groups of both compounds can also quantitatively react with hydroxylamine hydrochloride. Therefore these reactions may be employed to analytical procedure, including determination of hydroxyl and carbonyl groups. The 2, 4-dinitrophenyl hydrazones (DNP) of both compounds were prepared by the standard method. The melting points and N-contents of corresponding DNP were very close and ultraviolet absorption spectroscopy which indicates the electronic transition in the DNP molecule was perfectly agreed together. It came to conclution that DNP of acyloins are identical with DNP of α-diketones.
In glacial acetic acid solution vicinal functional groups of both compounds were quantitatively oxidized by periodic acid. On the other hand the reaction with periodic acid in the 99% ethanol solution was different in the case of acyloins and α-diketones. Namely, α-diketones cannot be oxidized, though acyloins can be easily done. It is possible to determine the acyloins in the presence of the α-diketones by nonaquous acid-base titration of formed fatty acids.
The infrared spectroscopy of both compounds was discussed.