[EN] THIONOLACTONES, PROCESSES OF SYNTHESIS, USES AS COMONOMERS AND FOR POLYMER FUNCTIONALIZATION AND DEGRADATION [FR] THIONOLACTONES, PROCÉDÉS DE SYNTHÈSE, UTILISATIONS EN TANT QUE COMONOMÈRES ET POUR LA FONCTIONNALISATION ET LA DÉGRADATION DE POLYMÈRES
摘要:
The instant invention relates to thionolactone compounds useful as comonomers to introduce weak bonds for polymer degradation or functionalization. The invention is also directed to processes for the preparation of said compounds, notably by thionation of the corresponding lactones. The invention is furthermore directed to uses of said thionolactones as comonomers, copolymers made from these comonomers, and processes for the preparation of said copolymers.
6-Oxocyclohexa-2,4-dienylideneketene: A Highly Reactive α-Oxoketene
作者:Regina C.-Y. Liu、Janusz Lusztyk、Michael A. McAllister、Thomas T. Tidwell、Brian D. Wagner
DOI:10.1021/ja980060t
日期:1998.7.1
The title ketene 2 has been generated by laser flash photolysis and observed in solution for the first time, using time-resolvedinfraredspectroscopy. The kinetics of the reactivity of 2 with H2O, MeOH, and Et2NH with relative reactivities of 1.0, 2.0, and 73 have been measured. These are the firstdirect measurements of the reactivities of a ketene with these different nucleophiles under the same
been developed where salicylic acid ketals react with alkynes to afford substituted chromones. A mechanistic rationale is proposed, implying beta-elimination of ketone from ring strained seven-membered nickelacycle to generate a five-membered oxa-nickelacycle intermediate.
Transition-Metal-Free Dehydrogenative Cyclization via α-Csp3–H Activation of Ethers and Thioethers
作者:Ranjan Jana、Kartic Manna、Hasina Mamataj Begam
DOI:10.1055/a-2017-6065
日期:——
S-alkylated salicylic or thiosalicylicacid derivatives to access 4H-benzo[d][1,3]dioxin-4-ones or 4H-benzo[d][1,3]oxathiin-4-ones, respectively. The oxidative cyclization of salicylic acid derivatives proceeds through a radical pathway at 110 °C. In contrast, the cyclization of the thiosalicylicacids proceeds smoothly at room temperature via an ionic pathway. Notably, the overall reactions are fast, completed
我们在此报道了四乙基溴化铵催化 O- 或 S- 烷基化水杨酸或硫代水杨酸衍生物的分子内氧化环化以获得 4 H -苯并[ d ] [1,3] 二恶英-4-酮或 4 H -苯并[ d ] [ 1,3]oxathiin-4-ones,分别。水杨酸衍生物的氧化环化在 110 °C 通过自由基途径进行。相反,硫代水杨酸的环化在室温下通过离子途径顺利进行。值得注意的是,整体反应速度快,反应时间短,产品收率高,季碳中心形成顺利。
Electrochemical Lactonization Enabled by Unusual Shono-Type Oxidation from Functionalized Benzoic Acids
A novel method for electrochemical lactonization via C(sp3)–H functionalization was developed. This metal- and oxidant-free strategy enabled the efficient synthesis of various lactones. Gram-scale reaction and derivatization of the lactone product demonstrated the synthetic utility of this methodology. Mechanistic studies using control experiments and CV curves elucidated the proposed intramolecular
开发了一种通过 C( sp 3 )–H 官能化进行电化学内酯化的新方法。这种不含金属和氧化剂的策略能够有效合成各种内酯。内酯产物的克级反应和衍生化证明了该方法的合成效用。使用对照实验和 CV 曲线进行的机理研究阐明了所提出的分子内 HAT 和氧化环化途径。通过这种电化学方法实现了不寻常的肖诺型氧化,无需传统的亲核加成过程。
The Reaction of Salicyclic Acids with Aldehyde Diacetates