Patent GB-929457-A (GB)
Title: Substituted pyridazones and plant-treating compositions containing them
Inventor: REICHENEDER FRANZ
IPC: C07D237/16
Filed: 1961-02-16
Abstract: The invention comprises substituted pyridazones of formula <FORM:0929457/IV(a)/1> in which A denotes a hydrogen atom, B denotes a hydroxyl group, or A and B together denote an oxo radical (= o), R denotes a hydrogen atom, a linear or branched alkyl group, a linear or branched halogensubstituted alkyl group, a halogen-substituted phenoxy- or an alkylhalo-phenoxy-alkyl group, an alkenyl group, an aralkyl group, the group <FORM:0929457/IV(a)/2> when A and B together represent an oxo radical, a phenyl group or a halogen-substituted phenyl group, and D denotes a phenyl group or a cycloalkyl group. The compounds can be prepared by reacting aminopyridazones of formula <FORM:0929457/IV(a)/3> with aldehydes, carboxylic acids or carboxylic acid derivatives having the formula RCOX in which R has the meaning given above and X is H, Cl, Br, OH or the group -OCOR.  For example, 1-phenyl-4-chloroacetyl-amino-5-chloropyridazone-6 is obtained by treating the corresponding 4-amino compound with chloroacetyl chloride.  The 4-amino starting compound may be obtained by reacting the corresponding 4-chloro compound with ammonia in methanol.  The compounds of the invention are effective herbicides and can also be used to influence plant growth in other ways (see Groups I and VI). Several compounds are specified, typical examples being:-1-phenyl-4-hydroxy-methylamino-5-chloropyridazone-6, 1-phenyl-4-b ,b , b - trichloroa -hydroxyethylamino- 5-chloropyridazone-6, 1-phenyl- 4-a - chloro-n-butyrylamino-5-chloropyridazone-6, 1-phenyl-4-(21-methyl-41-chlorophenoxy) - acetylamino-5-chloropyridazone-6, N,N1-bis- [1-phenyl-5-chloropyridazone-6-yl-4]-oxalic acid diamide, and 1-cyclooctyl- 4-chloroacetylamino-5-chloropyridazone-6.ALSO:Compositions for influencing plant growth comprise as the active ingredient a substituted pyridazene of formula <FORM:0929457/I/1> in which A denotes a hydrogen atom, B denotes a hydroxyl group, or A and B together denote an oxo radical (= O), R denotes a hydrogen atom, a linear or branched alkyl group, a linear or branched halogen-substituted alkyl group, a halogen-substituted phenoxy-or an alkyl-halophenoxy-alkyl group, an alkenyl group, an aralkyl group, the group <FORM:0929457/I/2> when A and B together represent an oxo radical, a phenyl group or a halogen-substituted phenyl group, and D denotes a phenyl group or a cycloalkyl group.  Solutions, emulsions, suspensions or dusting agents may be used.  The carrier may be phytotoxic, e.g. high boiling mineral oil fractions or chlorinated hydrocarbons. Other carriers include coal tar oils, vegetable and animal oils, hydrocarbons, alcohols, ketones, ethers, water and solid carriers. Wetting agents, emulsifying agents, dispersing agents, fatty acids, resins and protective colloids may be present as may bactericides, fungicides or fertilizers.  The agents may be used for dehydration, acceleration of ripening by premature desiccation, reduction of fruit setting, retardation of flowering, prolongation of harvesting period and store life, and for promotion of germination or rooting.ALSO:Herbicidal compositions comprise a substituted pyridazone of formula <FORM:0929457/VI/1> in which A denotes a hydrogen atom, B denotes a hydroxyl group, or A and B together denote an oxo radical (=O), R denotes a hydrogen atom, a linear or branched alkyl group, a linear or branched halogen-substituted alkyl group, a halogen-substituted phenoxy- or an alkylhalophenoxy-alkyl group, an alkenyl group, an aralkyl group, the group <FORM:0929457/VI/2> when A and B together represent an oxo radical, a phenyl group or a halogen-substituted phenyl group, and D denotes a phenyl group or a cycloalkyl group.  Solutions, emulsions, suspensions or dusting agents may be used.  The carrier may be phytotoxic, e.g. high boiling mineral oil fractions or chlorinated hydrocarbons. Other carriers include coal tar oils, vegetable and animal oils, hydrocarbons, alcohols, ketones, ethers, water and solid carriers.  Wetting agents, emulsifying agents, dispersing agents, fatty acids, resins and protective colloids may be present as may bactericides, fungicides or fertilizers.  The agents may be used as total or selective herbicides, and for dehydration, acceleration of ripening by premature desiccation, reduction of fruit setting, retardation of flowering and prolongation of harvesting period and store life.