19357-06-3Relevant academic research and scientific papers
Facile syntheses and characterization of hyperbranched poly(ester-amide)s from commercially available aliphatic carboxylic anhydride and multihydroxyl primary amine
Li, Xiuru,Zhan, Jie,Li, Yuesheng
, p. 7584 - 7594 (2007/10/03)
A new method for synthesis of novel hyperbranched poly(ester-amide)s from commercially available AA′ and CBx type monomers has been developed on the basis of a series of model reactions. The hyperbranched poly(ester-amide)s with multihydroxyl end groups are prepared by thermal polycondensation of carboxyl anhydrides (AA′) and multihydroxyl primary amine (CBx) without any catalyst and solvent. The reaction mechanism in the initial stage of polymerization was investigated with in situ 1H NMR. In the initial stage of the reaction, primary amino groups of 2-amino-2-ethyl-1,3-propanediol (AEPO) or tris(hydroxymethyl)aminomethane (THAM) react rapidly with anhydride, forming an intermediate which can be considered as a new ABx type monomer. Further self-polycondensation reactions of the ABx molecules produce hyperbranched polymers. Analysis using 1H and 13C NMR spectroscopy revealed the degree of branching of the resulting polymers ranging from 0.36 to 0.55. These hyperbranched poly(ester-amide)s contain configurational isomers observed by 13C and DEPT 13C NMR spectroscopy, possess high molecular weights with broad distributions and display glass-transition temperatures (Tgs) between 7 and 96°C. The thermogravimetric analytic measurements revealed the decomposition temperature at 10% weight-loss temperatures (Td10%) ranging from 212 to 325°C. Among the hyperbranched poly(ester-amide)s obtained, the polymers with cyclohexyl molecular skeleton structure exhibit the lowest branching degree, the highest glass-transition temperatures, and the best thermal stability.
The reaction of phthalidylidene dichloride with primary amines. Synthesis and X-ray molecular structure of N-substituted phthalisoimides
Guirado, Antonio,Zapata, Andres,Ramirez De Arellano, M. Carmen
, p. 5305 - 5324 (2007/10/03)
An efficient method for the synthesis of N-substituted phthalisoimides, by reaction of phthalidylidene dichloride with primary amines, is described. The reactions with arylamines, arylenediamincs and alkylenediamines lead to the corresponding phthalisoimides or bisphthalisoimides in nearly quantitative yields. However, the reactions with alkylamines are not useful because of the relatively high nucleophilicity of alkylamines. Certain particular behaviours of arylamines, associated with the presence of specific ortho-substituents have been found. The reactions of arylamines bearing an o-hydroxymethyl group provide a convenient method for preparing 2-benzoxazinylbenzoic acids. The X-ray crystallographic structures of N-(2-methoxyphenyl)phthalisoimide 3a and 2-(4H-3.1-benzoxazin-2-yl)benzoic acid 15a have been determined.
