Synthesis and insecticidal activity of n-acyl-n-methyl carbamates

✍ Scribed by J. Fraser; I. R. Harrison; S. B. Wakerley

• Publisher: John Wiley and Sons
• Year: 1968
• Tongue: English
• Weight: 482 KB
• Volume: 19
• Category: Article
• ISSN: 0022-5142
• DOI: 10.1002/jsfa.2740191302

✦ Synopsis

Methods of synthesis and insecticidal properties of a series of aryl N-acyl-N-methylcarbarnates are described. There is evidence to suggest that the usual mode of action involves de-acylation within the insect, although the acyl group may initially aid penetration to the site of action. An unexpected finding was that the acyl derivatives were generally less toxic to mammals than the parent carbarnates. The persistence of 3-s-butylphenyl N-methylcarbarnate on foliage was considerably improved by the introduction of a phenoxyacetyl group. However, acylation did not improve the outstanding activity and persistence on sheep fleece of the blowfly larvicide Butacarb (3,5-di-t-butylphenyl N-methylcarbarnate).

Preparation

A great deal is already known about the biological effects of varying the nuclear substituents in aryl N-methy1carbamates.l The present investigation, however, was directed towards modification of the carbamoyl moiety.