Synthesis of 2-arylhydrazono-4-chloro-3-oxobutanoates existing as (E)/(Z)-hydrazone isomers in solution: Correlation between equilibrium constants and substituent constants
作者:Chihaya Kawamura、Kiminari Yoshida、Naoki Yamazaki、Noriko Sato、Kenichiro Nagai、Eisuke Kaji、Yoshihisa Kurasawa
DOI:10.1016/j.molstruc.2019.126960
日期:2020.1
found to exist as two isomers between the (E)- and (Z)-hydrazone forms in DMSO‑d6 solution. The equilibrium constants K = [(Z)-form]/[(E)-form]: (8.0–3.4) at 30 °C} were clarified to correlate with the substituent constants of R (σp: 0.78 to −0.27) in the aryl group of compounds 10a-i, wherein the correlation coefficient was 0.99. The preponderance of the (Z)-hydrazone isomers in compounds 10a-i was
摘要 发现通过 4-氯-3-氧代丁酸乙酯与 4-取代的苯重氮氯化物反应合成的各种 2-芳基肼基-4-氯-3-氧代丁酸酯 10a-i 以两种异构体形式存在于 (E)- 和(Z)-腙在 DMSO-d6 溶液中形成。平衡常数 K = [(Z)-form]/[(E)-form]: (8.0–3.4) at 30 °C} 被阐明与 R 的取代基常数相关(σp:0.78 到 -0.27)在化合物10a-i的芳基中,相关系数为0.99。假设化合物 10a-i 中 (Z)-腙异构体的优势由 4-氯取代基引导,而不太稳定的 (E)-腙异构体的比例随着 σp 值的降低和温度的升高而逐渐增加.