N-(3-substituted oxyphenyl)tetrahydrophthalimides and herbicidal composition

A method of controlling weeds in the cultivation of a crop plant by applying a herbicidally effective amount of an N-(3-substituted oxyphenyl)-3,4,5,6-tetrahydrophthalimide of the formula:

• ##STR441## wherein X and Y each represent hydrogen or halogen;
• ##STR442## or --CN;
• R.sup.1 is hydrogen or C.sub.1-10 alkyl, phenyl chlorophenyl, bromophenyl, dichlorophenyl, methylchlorophenyl, methylphenyl or nitrophenyl;
• R.sup.2 is hydrogen or C.sub.1-4 alkyl;
• R.sup.3 is hydrogen or a C.sub.1-12 straight or branched alkyl, C.sub.2-5 alkenyl, C.sub.2-5 alkynyl, C.sub.1-5 haloalkyl, C.sub.3-4 haloalkenyl, C.sub.2-4 cyanoalkyl, C.sub.2-4 hydroxyalkyl, C.sub.3-6 alkoxyalkyl, C.sub.5-8 alkoxyalkoxyalkyl, C.sub.7-10 alkoxyalkoxyalkoxyalkyl, C.sub.3-8 alkylthioalkyl, C.sub.4-8 cycloalkyl, C.sub.7-9 aralkyl, chlorobenzyl, bromobenzyl, phenyl, .gamma.-butyrolactone optionally substituted by methyl, an alkali metal cation, an alkaline earth metal cation, ammonium cation, or an ammonium cation having 1 to 4 alkyl substituents, wherein the total carbon atom content of the ammonium cation is 1 to 9 carbon atoms;
• R.sup.4 is C.sub.1-12 alkyl, C.sub.3-6 alkoxycarbonylalkyl or benzyl;
• R.sup.5 is hydrogen or methyl;
• R.sup.6 is methyl or phenyl;
• R.sup.7 and R.sup.8 can be the same or different and each is hydrogen, C.sub.1-10 branched or straight chain alkyl, C.sub.2-5 alkenyl, C.sub.2-5 alkynyl, C.sub.2-6 haloalkyl, C.sub.2-6 hydroxyalkyl, alkoxyalkyl, aralkyl, phenyl, chlorophenyl, bromophenyl, methylphenyl, methoxyphenyl, pyrimidine, thiazole, pyridine, C.sub.1-6 alkoxy, C.sub.2-4 alkenyloxy, amino, methylamino, phenylamino, dimethylamino, C.sub.1-4 alkanesulfonyl, benzenesulfonyl, toluenesulfonyl, chlorobenzenesulfonyl, methoxybenzenesulfonyl or cyclohexyl;
• and ##STR443## wherein R.sup.7 and R.sup.8 together form a piperidine, or optionally together with an oxygen form a morpholine, isoxazolidine, or tetrahydroisoxazine ring;
• and m and n each represent an integer of 1 to 3.