Acid- and base-catalyzed hydrolysis of chloroacetamide herbicides

Daniel L. Carlson, Khoi D. Than, A. Lynn Roberts

Research output: Contribution to journalArticle

23 Scopus citations

Abstract

Despite the prevalence of chloroacetamides as herbicides, little is known about the rates or products of acid- or base-catalyzed hydrolysis of these compounds. Mechanisms of acid-catalyzed reactions may parallel those catalyzed by (hydr)oxide minerals, while base-catalyzed processes have as important counterparts reactions with environmental nucleophiles (such as reduced sulfur species). The current study systematically investigates how the structure of nine chloroacetamides affects their reactivity in 2 N NaOH, 2 N HCl, or 6 N HCl at 25 or 85°C. Base-catalyzed hydrolysis proceeds either through an intermolecular SN2 reaction to hydroxy-substituted derivatives or (in a few cases) through amide cleavage, while both amide and ether group cleavages are observed under acidic conditions. Our results reveal that subtle differences in chloroacetamide structure [notably the type of (alkoxy)alkyl substituent] can dramatically influence reactivity and reaction mechanism. Hydroxy-substituted, morpholinone, and secondary aniline derivatives were identified upon reaction for several years in deionized water at circumneutral pH.

Original languageEnglish (US)
Pages (from-to)4740-4750
Number of pages11
JournalJournal of Agricultural and Food Chemistry
Volume54
Issue number13
DOIs
StatePublished - Jun 28 2006
Externally publishedYes

Keywords

  • Acetochlor
  • Alachlor
  • Butachlor
  • Chloroacetanilides
  • Dimethachlor
  • Dimethenamid
  • Herbicide degradates
  • Metolachlor
  • Pretilachlor
  • Propachlor

ASJC Scopus subject areas

  • Chemistry(all)
  • Agricultural and Biological Sciences(all)

Fingerprint Dive into the research topics of 'Acid- and base-catalyzed hydrolysis of chloroacetamide herbicides'. Together they form a unique fingerprint.

  • Cite this