Cyclization of arylhydrazones of cross-conjugated enynones: synthesis of luminescent styryl-1<i>H</i>-pyrazoles and propenyl-1<i>H</i>-pyrazoles
作者:Radik N. Itakhunov、Ivan S. Odin、Dmitry M. Gusev、Stanislav A. Grabovskiy、Kareem V. Gordon、Anna V. Vologzhanina、Sergey A. Sokov、Ilya M. Sosnin、Alexander A. Golovanov
DOI:10.1039/d2ob01427k
日期:——
5-disubstituted pent-1-en-4-yn-1-ones with arylhydrazines in acidified alcohol results mainly in the formation of the corresponding arylhydrazones with traces of the side products of cyclization at the double bond – 1,5-diaryl-3-(arylethynyl)-4,5-dihydro-1H-pyrazoles (pyrazolines). Arylhydrazones are cyclized only by refluxing in high-boiling polar solvents (DMF and ethylene glycol), with the selective formation
1,5-二取代的 pent-1-en-4-yn-1-ones 与芳基肼在酸化酒精中的缩合主要导致相应的芳基腙的形成,在双键处有痕量的环化副产物 – 1,5 -二芳基-3-(芳基乙炔基)-4,5-二氢-1 H-pyrazoles (pyrazolines). Arylhydrazones are cyclized only by refluxing in high-boiling polar solvents (DMF and ethylene glycol), with the selective formation of 1,5-disubstituted 3-styrylpyrazoles in up to 77–95% yields. Thermodynamically, the cyclization of arylhydrazones at the triple bond is the
Addition of Benzenethiols to Silicon-Containing Enynes and Enynones
作者:S. A. Sokov、K. V. Gordon、S. S. Zlotskii、A. A. Golovanov
DOI:10.1134/s1070428024010068
日期:2024.1
malonate and Meldrumʼs acid, as well as cross-conjugated enynones, containing Me3Si, Et3Si, and t-BuMe2Si groups reacted with 4-methyl-, 4-methoxy-, and 4-chlorobenzenethiol under basic conditions to give the corresponding addition products with buta-1,3-diene and penta-1,4-dien-3-one fragments with high stereoselectivity. The thiylation products of enyne derivatives of dimethyl malonate and Meldrumʼs acid
摘要 丙二酸二甲酯和 Meldrum's 酸的亚丙炔衍生物,以及含有 Me 3 Si、Et 3 Si 和t -BuMe 2 Si 基团的交叉共轭烯酮,在 4-甲基-、4-甲氧基-和 4-氯苯硫醇的作用下反应与丁-1,3-二烯和五-1,4-二烯-3-酮片段产生具有高立体选择性的相应加成产物的基本条件。丙二酸二甲酯和 Meldrum 酸的烯炔衍生物的硫酰化产物保留了三烷基甲硅烷基,而苯硫酚与 5-(三烷基甲硅烷基)-1-苯基戊-1-en-4-yn-3-酮的加成伴随着脱甲硅烷基化。已经确定了所述反应的一些机理特征,并开发了含硫多不饱和化合物的立体选择性合成方法。
Yoshikawa, Takashi; Mori, Seiji; Shindo, Mitsuru, Journal of the American Chemical Society, 2009, vol. 131, p. 2092 - 2093