Abstract: In order to synthesize N-isopropyl-N'-o-carbomethoxyphenylsulphamide, sulphuric chlorohydrin is reacted with a pyridic base between -10.degree. and 50.degree. C., after which anthranilic acid methyl ester is firstly added at 0.degree.-60.degree. C., followed by isopropylamine at 0.degree.-60.degree. C., and finally phosphoric anhydride at 20.degree.-80.degree. C., the product being precipitated by dilution with water and recovered by filtration.

Abstract: A process for producing tricyclohexyl tin derivatives, consists of a first phase in which Grignard reagent and tin tetrahalogenide are caused to react by feeding them into a reaction vessel in a molar ratio of 3:1, and a second phase in which after hydrolysis and anhydridization of the condensation mass, further Grignard reagent is added in an amount such as to maintain the total molar ratio, between the Grignard reagent and the tin tetrahalogenide, between 3.5:1 and 3.9:1.

Abstract: The compound 5-amino-4-chloro-2-phenyl-3(2H)-pyridazinone free from 5-chloro-4-amino-2-phenyl-3(2H)-pyridazinone is used as selective weed-killer in a remarkably more efficacious and remarkably less phytotoxical way than the presently known "pyrazon" (mixture of 5-amino-4-chloro-2-phenyl-3(2H)-pyridazinone and 5-chloro-4-amino-2-phenyl-3(2H)-pyridazinone). The 5-amino-4-chloro-2-phenyl-3(2H)-pyridazinone is obtained from pyrazon by treating said pyrazon with a mineral acid of pre-fixed concentration, obtaining a suspension and filtering such a suspension. The use thereof as weed-killer is carried out in suitable formulations.

Abstract: A new heterocyclic chemical compound useful in the field of agricultural applications and in that of coloring substances has the formula ##STR1## (6-phenyl-[1,2,3]-oxadiazolo-(4,5 d)-pyridazine-7(6H)-one).

Abstract: In a process for obtaining 4,5-dichloro-2-phenyl-3(2H)-pyridazinone from 5-chloro-4-amino-2-phenyl-3(2H)-pyridazinone the 5-chloro-4-amino-2-phenyl-3(2H)-pyridazinone is diazotized in a first stage in accordance with the following reaction: ##STR1## the compound (I) being obtained by dilution with water and filtration. In a second stage of the process the compound (I) is reacted with thionyl chloride in accordance with the following reaction: ##STR2## the 4,5-dichloro-2-phenyl-3(2H)-pyridazinone being obtained by dilution with water and filtration.

Abstract: Process and apparatus for the production, in a continuous cycle, of cyclohexyl magnesium halides according to which cyclohexyl halide is fed from the bottom, at a constant rate, into a thermostatized column containing magnesium shavings fed from the top of the column itself, and the desired cyclohexyl magnesium halide is recovered in the top part of the column, the temperature of the column being kept at about 58.degree.-60.degree. C. and the cyclohexyl halide being fed in a solution of tetrahydrofuran.