Use as insecticides of esters of nitro(tetrahydro-2H-1,3-thiazin-2-ylidene)acetic acids

A method of killing insects which comprises contacting them with an insecticidally effective amount of a resonance hybrid in which the significant forms are represented by the formulae ##STR4## and the enol form represented by the formula ##STR5## wherein R contains up to thirty carbon atoms and is alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkylalkyl, alkadienyl, haloalkyl, haloalkenyl, mono- and poly-(alkoxy)alkyl, alkylthioalkyl, phenylthioalkyl, benzylthioalkyl, cyanoalkyl, hydroxyalkyl, alkylsulfinylalkyl, alkylsulfonylalkyl, phenyl or phenalkyl or either substituted on the ring by one to two of one or more of halogen, nitro, cyano, alkyl, phenyl, alkoxy or phenoxy;

• is aminoalkyl, --CH.sub.2 --NR.sup.3 R.sup.4, wherein m is one or two, R.sup.3 is alkyl, cycloalkyl, alkenyl, phenyl or phenalkyl, and R.sup.4 is hydrogen or one of the moieties represented by R.sup.3 ;
• or is --CH.sub.2 --R.sup.5, wherein n is zero, one or two, and R.sup.5 is a heteromonocyclic moiety with from five to six atoms in the ring, containing carbon atoms and one to two oxygen (--O--), sulfur (--S--) or nitrogen atoms (.dbd.N-- or --NH--) bonded to carbon in the ring.