75545-07-2Relevant academic research and scientific papers
Polymerization of 2,5-diaminoterephthalic acid-type monomers for the synthesis of polyamides containing ladder unit
Yokoyama, Akihiro,Kuramochi, Jinya,Kiyota, Ryohei,Kishimoto, Kazuki,Takaishi, Kazuto,Yokozawa, Tsutomu
, p. 2365 - 2372 (2017)
To synthesize ladder-type polyamides by construction of two amide bonds successively, 2,5-diaminoterephthalic acid derivatives bearing anthranilic acid ester and isatoic anhydride moieties were synthesized and their polymerization was investigated. Polymerization of the methyl ester monomer proceeded in the presence of lithium hexamethyldisilazide (LiHMDS) as a base in tetrahydrofuran (THF). However, mass spectroscopic analysis of the product suggested that not only the bis(trimethylsilyl)amide anion of LiHMDS but also the methoxide anion eliminated at the second amide-linkage formation reaction decomposed the isatoic anhydride unit of the growing oligomer by nucleophilic attack to disturb the polymerization. To reduce the nucleophilicity of the eliminated anion, methyl ester of the monomer was changed to phenyl ester and its polymerization was studied. The reaction conditions were optimized, and the best result was obtained when the polymerization was conducted in the presence of 1.0 equivalent of LiHMDS without additives in THF at 50?°C.
Solvatochromic fluorescent compound as well as preparation method and application thereof
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Paragraph 0092-0097, (2020/01/11)
The invention discloses a solvatochromic fluorescent compound as well as a preparation method and application thereof, and belongs to the technical field of synthesis of fluorescent compounds. The fluorescent compound is a single-benzene-ring fluorescent compound that is 2,5-diamino-1,4-dibenzoic acid. The fluorescent compound is diamine dibenzoic acid which is a single-benzene-ring fluorescent compound and is obtained by reaction of succinyl succinate with alkylamine, oxidization, hydrolysis and acidification. The compound has a relatively high fluorescence quantum yield and good photochemical stability; the fluorescence behavior of the fluorescent compound has extremely strong dependence on an organic solvent, particularly has remarkable distinguishing capability on alcohols, halogen-containing alkanes and other common organic solvents, has a wide emission peak distribution range, and can be used for a solvatochromic fluorescent probe material.
