チオセミカルバジド誘導体の研究 (第1報)
チオセミカルバジドのアシル化について
1958 年 78 巻 3 号 p. 280-283
詳細
1958 年 78 巻 3 号 p. 280-283
Reëxamination of acylation of thiosemicarbazide in acetone showed that 1-isopro-pylidene-2-acylthiosemicarbazide (II) forms as an intermediate, which undergoes hydrolysis and rearrangement of acyl group by the action of hydrochloric acid, formed as a by-product during heating in the final step, to produce 1-acylthiosemicarbazide (I). Therefore, presence of a dehydrochlorination agent, such as sodium carbonate, may stop the reaction at the stage of (II), while its absence will afford (I).
Benzoylation and phenylacetylation of thiosemicarbazide by the Schotten-Baumann reaction showed that the amount fo sodium hydroxide affected formation of the reaction product. In the benzoylation, yield of 1-benzoylthiosemicarbazide was poor when the molar ratio of thiosemicarbazide to sodium hydroxide was 1:1, affording several kinds of a by-product, while the amount of by-products decreased when the molar ratio became 1:2, and the yield of the 1-acyl compound became 61%. However, these conditions failed to suppress side reactions in the case of phenylacetylation.
