4-Substituted-5-cyano-7-nitro-2-(.alpha.,.alpha.-difluoroalkyl)benzimidaz oles

Compound of the formula ##SPC11##

• wherein Y represents
• a. hydrogen,
• b. chlorine,
• c. fluorine,
• d. trifluoromethyl, or
• e. pentafluoroethyl;
• and wherein R.sup.o and R.sub.1 are either taken separately, in which case each independently represents one of the following, subject to the limitation that at least one of R.sup.o and R.sup.1 contains more than 1 carbon atom and that R.sup.o and R.sup.1 together contain less than 9 carbon atoms:
• 1. hydrogen
• 2. alkyl
• 3. alkenyl containing more than 2 carbon atoms,
• 4. alkynyl containing more than 2 carbon atoms,
• 5. (fluoroalkyl)methyl wherein alkyl is C.sub.1 -C.sub.7, both inclusive, and bears at least one fluorine atom,
• 6. cycloalkyl of C.sub.3 -C.sub.8, both inclusive
• 7. cycloalkylloweralkyl, wherein cycloalkyl is of C.sub.3 -C.sub.6, both inclusive, and loweralkyl is of C.sub.1 -C.sub.4, both inclusive, or
• 8. loweralkylcycloalkyl, wherein cycloalkyl and loweralkyl are as defined in the preceding candidate moiety;
• or R.sup.o and R.sup.1 are taken together, in which case they jointly constitute, with the nitrogen atom to which they are attached, piperidino;
• and the alkali metal and alkaline earth metal salts thereof.