Acid- and base-catalyzed hydrolysis of chloroacetamide herbicides

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

Research output: Contribution to journalArticle

22 Citations (Scopus)

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

Fingerprint

Herbicides
Hydrolysis
herbicides
hydrolysis
amides
Amides
Acids
acids
chemical derivatives
Oxide minerals
oxide, hydroxide, and oxyhydroxide minerals
Derivatives
Nucleophiles
aniline
reaction mechanisms
Deionized water
Sulfur
Ether
Oxides
Minerals

Keywords

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

ASJC Scopus subject areas

  • Agricultural and Biological Sciences (miscellaneous)
  • Food Science
  • Chemistry (miscellaneous)

Cite this

Acid- and base-catalyzed hydrolysis of chloroacetamide herbicides. / Carlson, Daniel L.; Than, Khoi; Roberts, A. Lynn.

In: Journal of Agricultural and Food Chemistry, Vol. 54, No. 13, 28.06.2006, p. 4740-4750.

Research output: Contribution to journalArticle

Carlson, Daniel L. ; Than, Khoi ; Roberts, A. Lynn. / Acid- and base-catalyzed hydrolysis of chloroacetamide herbicides. In: Journal of Agricultural and Food Chemistry. 2006 ; Vol. 54, No. 13. pp. 4740-4750.
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