Abstract: The invention relates to new 2-cyanobenzimidazole derivatives.These compounds have the formula (II): ##STR1## with: n 0, 1 or 2,m 1 or 2,R halogen; lower alkyl or lower alkoxy or lower alkylthio, optionally halogenated; NO.sub.2 --, CN--,R' lower alkyl or lower cycloalkyl, optionally halogenated, amino optionally substituted with one or two alkyl radicals, or a nitrogen atom substituted with two radicals forming with this nitrogen atom a heterocycle which contains from 4 to 6 members and from 1 to 3 hetero atoms in the ring,R" optionally substituted phenoxy or optionally substituted phenylthio.They can be used in agriculture, especially for controlling phytopathogenic fungi.

Abstract: The invention relates to new 2-cyanoimidazopyridine derivatives.These compounds have the formula (I): ##STR1## in which: R.sub.1 represents an optionally halogenated lower alkyl or cycloalkyl radical or an amino radical optionally substituted by one or two lower alkyl radicals, one of the groups Z.sub.1, Z.sub.2, Z.sub.3 and Z.sub.4 represents a nitrogen atom and the others are chosen independently from the CH group and CR groups in which R represents a halogen atom or an optionally substituted lower alkyl, optionally substituted lower alkoxy, optionally substituted lower alkylthio, nitro or cyano radical.They can be used in agriculture for combating phytopathogenic fungi.

Abstract: The invention relates to new 2-cyanobenzimidazole derivatives.These compounds correspond to the formula (I): ##STR1## in which: n is 0, 1, 2 or 3,R is halogen; optionally halogen-substituted lower alkyl or alkylthio; lower alkoxy optionally substituted by one or more halogens or by the phenyl radical; lower alkenyl; lower alkynyl; amino optionally substituted by one or two alkyls; NO.sub.2 --; CN--; CNO--; NCS--; , SCN--; lower alkylsulphonyl; sulphamoyl optionally substituted by one or two alkyls; lower alkylsulphinyl; optionally substituted acyl; or alkoxycarbonyl, andR' is optionally halogen-substituted lower alkyl, amino optionally substituted by one or two alkyl radicals, or a nitrogen atom substituted by two radicals forming a heterorcyclic ring with this nitrogen atom, the heterocyclic ring containing from 4 to 6 ring members and from 1 to 3 hetero-atoms in the ring.They can be used in agriculture, in particular for combating phytopathogenic fungi and for combating mites.

Abstract: A polyfluorinated butadiene having the formula ##EQU1## wherein n and m are integers from 1 to 10 and n=m or n.noteq.m, is prepared by reductive coupling, exemplarily with copper, of the corresponding 1,2-bis(perfluoroalkyl)iodoethylene having the formula CF.sub.3 (CF.sub.2).sub.n CH = CI--(CF.sub.2).sub.m CF.sub.3. This iodoethylene is conveniently prepared by a simple addition reaction between a perfluoroalkyl iodide and a perfluoroalkyl acetylene. The perfluoralkylated butadienes are useful as transporters of dissolved gas, particularly of oxygen as in blood substitutes.