کد مقاله کد نشریه سال انتشار مقاله انگلیسی ترجمه فارسی نسخه تمام متن
5196271 1381378 1999 8 صفحه PDF سفارش دهید دانلود کنید
عنوان انگلیسی مقاله ISI
Cyclopolymerization: XXVI. Repeating unit structure of cyclopolymers derived from N-substituted-N-allyl-2-(methoxycarbonyl)allylamines and mechanism of intramolecular cyclization
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی آلی
پیش نمایش صفحه اول مقاله
Cyclopolymerization: XXVI. Repeating unit structure of cyclopolymers derived from N-substituted-N-allyl-2-(methoxycarbonyl)allylamines and mechanism of intramolecular cyclization
چکیده انگلیسی

NMR studies on completely cyclized polymers derived from N-substituted-N-allyl-2-(methoxycarbonyl)allylamines (1) were undertaken to determine the repeat cyclic unit. NMR techniques employed are two-dimensional INADEQUATE (Incredible Natural Abundance DoublE QUAntum Transfer Experiment), DEPT (Distortion Enhancement by Polarization Transfer) measurements, and those under suppressed nuclear Overhauser effect. These studies along with the comparison of the spectra of poly(1) with those of related compounds revealed that the poly(1) consists of two sets of five-membered rings. The main chain methylene carbons attached to the ring has a trans configuration for one of them and a cis arrangement for the other. The former was found to be a main component. The value 4.5 kJ/mol as the difference of the activation energy for the formation of the respective configuration, Ecis−Etrans, was obtained by the investigation of temperature effect. Comparison of these results with those reported so far for polymers with similar structures led to the conclusion that five-membered ring formation could be interpreted by a kinetic mechanism as in the radical cyclization reactions in low molecular weight compounds.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Polymer - Volume 40, Issue 25, December 1999, Pages 6947-6954
نویسندگان
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