67498-35-5Relevant articles and documents
A novel sublimable organic salt: Synthesis, characterization, thermal behavior, and catalytic activity for the synthesis of arylidene, heteroarylidene, and alkylidene malonates
Johari, Suzaimi,Zaharani, Lia,Gorjian, Hayedeh,Johan, Mohd R.,Khaligh, Nader G.
, p. 361 - 377 (2021/09/18)
A novel sublimable organic salt was synthesized, and its chemical structure was characterized by FTIR, 1D NMR, 2D NMR, and elemental analysis. In addition, the thermal phase transitions and thermal stability of new organic salt were investigated. The DSC and TGA results showed that the organic salt could convert into constituent molecules at dec. ~ 200?°C) under atmospheric pressure without forming the liquid phase. Then, it was recondensed to regenerate the initial organic salt in the cool part of the vial. Therefore, it can be a promising organic salt towards the regeneration of spent catalyst from synthesis processes when the reaction mixture contains poorly volatile components and includes its use in gas-phase procedures. Also, the catalytic efficiency of new organic salt was investigated in the Knoevenagel condensation reaction. A variety of substituted arylidene and alkylidene malonates were isolated in 78–95% yield within six hours.? Under the optimized reaction conditions, the current catalytic procedure exhibited superiority compared to the mixed piperazine/acetic acid, piperidine/acetic acid, and piperidinium acetate. There were no significant changes in the new organic salt chemical structure and catalytic activity even after the 5th run. This work revealed the importance of the existence of simultaneous hydrogen bond acceptor/donor groups in our environmentally friendly catalyst to promote the Knoevenagel condensation reaction without the use of metal-containing catalysts.
Acetal Addition to Electron-Deficient Alkenes with Hydrogen Atom Transfer as a Radical Chain Propagation Step
Chan, Wei Chuen,Vinod, Jincy K.,Koide, Kazunori
, p. 3674 - 3682 (2021/02/16)
We describe a visible-light-promoted addition of a hydrogen atom and an acetal carbon toward various electron-deficient alkenes. 1,3-Dioxolane is converted to its radical species in the presence of persulfate and an iridium catalyst upon visible light irradiation, which then reacts with electron-deficient alkenes. The reaction operates via a radical chain mechanism, a less commonly observed pathway for this class of transformation. Hydrogen atom transfer from 1,3-dioxolane to α-malonyl radicals is corroborated by experimental and density functional theory studies.
Indium(III)-catalyzed knoevenagel condensation of aldehydes and activated methylenes using acetic anhydride as a promoter
Ogiwara, Yohei,Takahashi, Keita,Kitazawa, Takefumi,Sakai, Norio
, p. 3101 - 3110 (2015/03/30)
The combination of a catalytic amount of InCl3 and acetic anhydride remarkably promotes the Knoevenagel condensation of a variety of aldehydes and activated methylene compounds. This catalytic system accommodates aromatic aldehydes containing a variety of electron-donating and -withdrawing groups, heteroaromatic aldehydes, conjugate aldehydes, and aliphatic aldehydes. Central to successfully driving the condensation series is the formation of a geminal diacetate intermediate, which was generated in situ from an aldehyde and an acid anhydride with the assistance of an indium catalyst.
