767-00-0Relevant articles and documents
Bis(4-cyanophenyl) phenyl phosphate as viscosity reducing comonomer for phthalonitrile resins
Terekhov,Aleshkevich,Afanaseva,Nechausov,Babkin,Bulgakov,Kepman,Avdeev
, p. 34 - 41 (2019)
Bis(4-cyanophenyl) phenyl phosphate (CPP) is introduced for the first time as a viscosity reducing comonomer for phthalonitrile resins. In comparison to the common phthalonitrile resins, the blends of CPP with 4,4′-[benzene-1,3-diylbis(oxy)]diphthalonitrile demonstrated advanced processing properties suitable for cost-effective injection processing (η as low as to 180 mPa?s at 100 °C). Thermal copolymerization was performed indicating complete inclusion of bis-benzonitrile CPP into the phthalonitrile network resulting in formation of thermosets with great thermal performance. Hydrolysis of CPP at pH 4, 7, and 10 was studied to confirm its suitability as a reactive diluent for phthalonitrile. Conversion vs. time plots were obtained via HPLC analysis, and pseudo-first order rate constants were determined in the range of 25–80 °C. The activation parameters were calculated from the Arrhenius equation.
Nickel-catalyzed deallylation of aryl allyl ethers with hydrosilanes
Ding, Guangni,Fan, Sijie,Wang, Jingyang,Wang, Yu,Wu, Xiaoyu,Xie, Xiaomin,Yang, Liqun,Zhang, Zhaoguo
supporting information, (2021/09/28)
An efficient and mild catalytic deallylation method of aryl allyl ethers is developed, with commercially available Ni(COD)2 as catalyst precursor, simple substituted bipyridine as ligand and air-stable hydrosilanes. The process is compatible with a variety of functional groups and the desired phenol products can be obtained with excellent yields and selectivity. Besides, by detection or isolation of key intermediates, mechanism studies confirm that the deallylation undergoes η3-allylnickel intermediate pathway.
Photocatalytic Reductive C-O Bond Cleavage of Alkyl Aryl Ethers by Using Carbazole Catalysts with Cesium Carbonate
Yabuta, Tatsushi,Hayashi, Masahiko,Matsubara, Ryosuke
, p. 2545 - 2555 (2021/02/01)
Methods to activate the relatively stable ether C-O bonds and convert them to other functional groups are desirable. One-electron reduction of ethers is a potentially promising route to cleave the C-O bond. However, owing to the highly negative redox potential of alkyl aryl ethers (Ered -2.6 V vs SCE), this mode of ether C-O bond activation is challenging. Herein, we report the visible-light-induced photocatalytic cleavage of the alkyl aryl ether C-O bond using a carbazole-based organic photocatalyst (PC). Both benzylic and non-benzylic aryl ethers underwent C-O bond cleavage to form the corresponding phenol products. Addition of Cs2CO3 was beneficial, especially in reactions using a N-H carbazole PC. The reaction was proposed to occur via single-electron transfer (SET) from the excited-state carbazole to the substrate ether. Interaction of the N-H carbazole PC with Cs2CO3 via hydrogen bonding exists, which enables a deprotonation-assisted electron-transfer mechanism to operate. In addition, the Lewis acidic Cs cation interacts with the substrate alkyl aryl ether to activate it as an electron acceptor. The high reducing ability of the carbazole combined with the beneficial effects of Cs2CO3 made this otherwise formidable SET event possible.