5024-81-7Relevant academic research and scientific papers
Synthesis of functionalized p-phenylene oxide oligomers
Wang, Leyong,Xi, Haitao,Sun, Xiaoqiang,Shen, Yingzhong,Yang, Yang,Pan, Yi,Hu, Hongwen
, p. 227 - 234 (2000)
Oligomers of p-phenylene oxides have been synthesized by coupling of substituted phenols and aryl bromides in the presence of cuprous chloride. The chain length varies from 2 to 5 phenyl rings functionalized at one end by an OH and OMe group and at the other end by an OH, OMe or NO2 functions. The oligomers could be used in material science and as building blocks in supramolecular chemistry. Methods for chemoselective demethylation of methoxy groups were developed.
Thermal transition behaviors, solubility, and mechanical properties of wholly aromatic para -, meta -poly(ether-amide)s: Effect on numbers of para -aryl ether linkages
Zhang, Wen-Qiang,Wang, Xiu-Li,Liu, Gui-Cheng,Chen, Li,Wang, Yu-Zhong
, p. 84284 - 84293 (2016/10/12)
In order to make clear how the numbers of para-aryl ether linkages affect the solubility, thermal transition behavior and mechanical properties of para-(p-PEAs), meta-poly(ether-amide)s (m-PEAs), a series of para-substituted aryl ether diamine monomers with 2, 3, 4 or 5 ether linkages were synthesized, and then reacted with terephthalic acid and isophthalic acid via the Yamazaki-Higashi phosphorylation method to prepare wholly aromatic PEAs. The PEAs with intrinsic viscosity values in the range of 0.81-1.16 dL g-1 were obtained and characterized by FT-IR, NMR, and elemental analysis. Although the Tgs and Tms of PEAs decrease with the increasing numbers of aryl ether linkages, their Tgs and Tms still are above 180 °C and 320 °C, respectively. p-PEAs have a high crystallinity making it difficult to dissolve them in common organic solvents even when 5 aryl ether linkages are introduced. Conversely, except for m-PEA5 with a lower polarity, the other m-PEAs show good solubility due to their low crystallinity. Besides, the decomposition temperatures at 5% weight loss of all PEAs exceed 430 °C and their residual yields at 700 °C are above 50% in N2, illustrating that they have excellent thermal stability. It is found that by casting m-PEAs DMAc solution in a dish, the transparent films with high Young's modulus (2.6-3.5 GPa) can be successfully obtained.
Synthesis and structure of cyclic oligo(p-phenylene oxide)s, -(C 6H4O)n- (n = 6-10)
Takeuchi, Daisuke,Asano, Itaru,Osakada, Kohtaro
, p. 8614 - 8617 (2007/10/03)
Stepwise growth of oligo(p-phenylene oxide)s and cyclization via the Ullmann coupling reaction by using CuI/N,N-dimethylglycine afforded cyclic oligo(p-phenyleneoxide)s, -(C6H4O)n-(n = 6-10). The structure of the new cyclophanes was determined by X-ray crystallography, which revealed that they have planar or slightly bent structures with diameters of 1.0-1.5 nm.
A convenient method for the preparation of 4-aryloxyphenols
Yeager,Schissel
, p. 63 - 68 (2007/10/02)
A convenient method for the preparation of 4-aryloxyphenols via the homologation of preformed phenols is described. Condensation of various 4-substituted phenols with either 4-fluorobenzaldehyde (8) or 4-fluoroacetophenone (9) yielded the corresponding 4-aryl-oxybenzaldehydes, 10, and acetophenones, 11, in 70-93% yield. Baeyer-Villiger oxidation of these materials with 3-chloroperoxybenzoic acid (MCPBA) yielded the corresponding 4-formyloxy and 4-acetoxyphenyl ethers which were hydrolyzed without purification to the desired 4-aryloxyphenols 12 in 72-94% yield. Both 4-fluorobenzaldehyde (8) and 4-fluoroacetophenone (9) are synthetically equivalent to the a4 umpoled synthon 6. Extension of this methodology of the preparation of 4,4'-[arylbis(oxy)]bisphenols from aromatic diols is also described. Condensation of various aromatic diols with 8 or 9 yielded the corresponding 4,4'-[arylbis(oxy)]bisbenzaldehydes 15 and acetophenones 16 in 71-89% yield. Baeyer-Villiger oxidation of these compounds with MCPBA yielded the desired 4,4'-[arylbis(oxy)]bisphenyl bisformates 17 and bisacetates 18 in 67-84% yield. Hydrolysis of these compounds afforded the desired 4,4'-[arylbis(oxy)bisphenols 19 in 70-91% yield.
