Sistema conjugado






Estrutura química do fenol


Um sistema conjugado ocorre em um composto químico onde os átomos unidos mediante ligação covalente com ligações simples e múltiplas alternantes (por exemplo, C=C-C=C-C) e com influência mútua para produzir uma região chamada deslocalização eletrônica. Nesta região, os elétrons não pertencem a uma só ligação ou átomo, mas sim a um grupo. Por exemplo, o fenol (C6H5OH) tem um sistema de 6 elétrons acima e abaixo do plano do anel, assim como também do grupo hidroxilo.


O sistema conjugado resulta numa deslocalização geral dos elétrons através de todos os orbitais p alinhados paralelamente, o que incrementa a estabilidade e diminui a energia global da molécula.[1]



Referências




  1. ↑ March Jerry; (1985). Advanced Organic Chemistry reactions, mechanisms and structure (3rd ed.). New York: John Wiley & Sons, inc. ISBN 0-471-85472-7



Ver também |



  • Ressonância

  • Hiperconjugação

  • Conjugação cruzada



  • Portal da química



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