The Cu-catalyzed aerobic oxidative esterification of simple ketones via C-C bond cleavage has been developed. Varieties of common ketones, even inactive aryl long-chain alkyl ketones, are selectively converted into esters. The reaction tolerates a wide range of alcohols, including primary and secondary alcohols, chiral alcohols with retention of the configuration, electron-deficient phenols, as well
已经开发了通过 CC 键裂解的 Cu 催化的简单酮的有氧氧化酯化。各种常见的酮,甚至是惰性的芳基长链烷基酮,都被选择性地转化为酯。该反应耐受多种醇,包括伯醇和仲醇、保留构型的手性醇、缺电子酚以及各种天然醇。使用廉价的铜催化剂、广泛的基材范围以及中性和露天条件使该协议非常实用。(18)O 标记实验表明,在这种转化过程中发生了氧化作用。初步机制研究表明,该过程主要涉及两条新途径。
Photocatalytic esterification under Mitsunobu reaction conditions mediated by flavin and visible light
作者:M. März、J. Chudoba、M. Kohout、R. Cibulka
DOI:10.1039/c6ob02770a
日期:——
The usefulness of flavin-based aerial photooxidation in esterification underMitsunobu reaction conditions was demonstrated, providing aerial dialkyl azodicarboxylate recycling/generation from the corresponding dialkyl hydrazine dicarboxylate. Simultaneously, activation of triphenylphosphine (Ph3P) by photoinduced electron transfer from flavin allows azo-reagent-free esterification. An optimized system
Flavin Catalysis Employing an N(5)-Adduct: an Application in the Aerobic Organocatalytic Mitsunobu Reaction
作者:Michal März、Martin Babor、Radek Cibulka
DOI:10.1002/ejoc.201900397
日期:2019.6.2
An N(5)‐flavin adduct was utilized in a catalytic Mitsunobureaction with triphenylphosphane (triphenylphosphine), in which flavin acts as a Mitsunobu reagent instead of dialkyl azodicarboxylate. Flavin is used in a catalytic amount after regeneration by dioxygen.
A hydraulic fluid of the present invention has low energy loss due to compression and exhibits excellent responsiveness when being used in a hydraulic circuit. Consequently, the hydraulic fluid realizes energy-saving, high-speed operation and high precision of control in the hydraulic circuit.