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Reaction Kinetics and Catalysis Letters

, Volume 21, Issue 4, pp 437–443 | Cite as

A search for resonance effects in the kinetics of chromic acid oxidation of a series of benzaldehyde and substituted benzaldehydes. A reinvestigation

  • P. Musala Reddy
  • V. Jagannadham
  • B. Sethuram
  • T. Navaneeth Rao
Article

Abstract

The kinetics of oxidation of a series of meta and para substituted benzaldehydes by chromic acid has been re-investigated in acetic acid water mixture with a view on the search for resonance effects of para substituents. The overall order of the reaction is two, first order in each reactant at constant acidity. The products of oxidation were found to be the corresponding carboxylic acids. Hammett's reaction constants (ρm) and (ρp) for meta and para substituents were calculated separately and found to be 0.851 and 1.23, respectively. The reason for the higher ρp value with respect to ρm is discussed. The resonance parameters for para substituents were calculated and discussed.

Keywords

Oxidation Acetic Acid Catalysis Acidity Carboxylic Acid 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Abstract

Кинетика окисления ряда мета и паразамещенных бензальдегидов хромовой кислотой была исследована в водной уксусной кислоте с целью определения резонансных эффектов паразаместителей. Суммарный порядок реакции равен 2, а при постоянной кислотности наблюдался первый порядок по каждому реагенту. Продуктами окисленя оказались соответствующие карбоксильные кислоты. Были рассчитаны константы Гаммета для мета- и паразамещенных производных: ρМ=0,851 и ρП=1,23. Обсуждаются причины повышенного значения ρП по сравнению с ρМ. Были рассчитаны и обсуждаются резонансные параметры паразаместителей.

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Copyright information

© Akadémiai Kiadó 1982

Authors and Affiliations

  • P. Musala Reddy
    • 1
  • V. Jagannadham
    • 1
  • B. Sethuram
    • 2
  • T. Navaneeth Rao
    • 2
  1. 1.Department of ChemistrySardar Patel CollegeSecunderabad
  2. 2.Department of ChemistryOsmania UniversityHyderabadIndia

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