Abstract: Novel 1,3,4-oxadiazoline-5-one derivatives, their preparation and the insecticidal compositions in which they are present are disclosed. The novel 1,3,4-oxadiazoline-5-one derivatives correspond to the formula: ##STR1## in which: X represents a halogen atom,R.sub.1, R.sub.2 and R.sub.3, which may be identical or different, each represent a hydrogen atom or an alkyl radical containing from 1 to 3 carbon atoms,R.sub.4 represents a halogen atom, an alkyl radical containing from 1 to 3 carbon atoms or an alkoxy radical containing from 1 to 3 carbon atoms, andn represents an integer which is 0, 1, 2, 3 or 4, with the proviso that if n is 2, 3 or 4, the substituents R.sub.4 are identical or different. These compounds are useful as agricultural insecticides.

Abstract: Dextrorotatory 2-phenoxypropionic acids are made by heating an alkali metal salt of dextrorotatory 2-chloropropionic acid with an alkali metal phenate in an inert organic solvent of high boiling point under reflux.

Abstract: A process for the manufacture of 3-(3,5-dichlorophenyl)-hydantoin comprises cyclizing 3-(3,5-dichloro-phenyl)-ureidoacetic acid in the presence of a catalytic amount relative to the ureidoacetic acid of an acid dehydrating agent and in the presence of an organic solvent which forms an azeotrope with water; the water formed during the reaction is eliminated by azeotropic distillation.

Abstract: Derivatives of 3-(3,5-dichlorophenyl)-ureidoacetic acid, of the general formula: ##STR1## wherein R is a linear or branched alkyl radical containing 1 to 4 carbons, or an alkenyl of 2 to 4 carbons, is obtained by the action of an inorganic base such as sodium hydroxide, potassium hydroxide or ammonia, in an aqueous-organic solution such as a mixture of ethanol and water, on a hydantoin derivative of the general formula: ##STR2## IN WHICH R is defined as above. The compounds (I) have fungicidal activity.

Abstract: Fungicidal 1-carbamoyl-3-(3,5-dichlorophenyl)-hydantoins are prepared by reacting 3 mols an isocyanate of the general formula R -- N .dbd. C .dbd. 0 (wherein R is alkyl of 1-4 carbons or alkenyl of 2-4 carbons) with one mol of 3-(3,5-dichlorophenyl)-ureidoacetic acid in an anhydrous medium in the presence of an organic base.

Abstract: Organophosphorus compounds of the formula ##STR1## wherein R is alkyl of 1-4 carbons, R.sub.1 is hydrogen, halogen, nitro, trifluoromethyl, or an alkyl, alkoxy or alkylthio radical of 1-4 carbons, and X and Y are sulfur or oxygen. The compounds are useful as insecticides and acaricides.

Abstract: Pyrazoline compounds of the formula:- ##SPC1##Wherein Ar represents phenyl optionally substituted by at most three atoms or radicals selected from halogen, alkyl and alkoxy of 1 through 4 carbon atoms, trifluoromethyl and nitro, and R.sub.1 and R.sub.2 represent hydrogen or methyl, are new compounds possessing insecticidal, acaricidal and nematicidal properties.