Transmission of Substituent Effects through Oxygen and Sulfur Atoms. III. The Ionization Equilibrium Constants of Ring-substituted<i>cis</i>-β-Phenoxyacrylic Acids
作者:Okitsugu Kajimoto、Masaru Kobayashi、Takayuki Fueno
DOI:10.1246/bcsj.46.1425
日期:1973.5
cis-β-Phenoxyacrylic acid and several of its ring-substituted derivatives were prepared, and their ionization constants were determined in 50% ethanol–water at 25 °C. The Hammett ρ value for the ionization of these acids, 0.439, is smaller than that reported for cis-β-phenylthioacrylic acids, 0.531. The greater efficiency of the sulfur atom in transmitting the substituent effects is explainable in terms
制备了顺式-β-苯氧基丙烯酸及其几种环取代衍生物,并在 25°C 下在 50% 乙醇-水中测定了它们的电离常数。这些酸的电离的哈米特 ρ 值 0.439 小于报道的顺式-β-苯基硫代丙烯酸的值 0.531。硫原子在传递取代基效应方面的更高效率可以用硫原子在形成的硫代丙烯酸酯阴离子中的“通过共轭”来解释。