Abstract:
The invention provides a process for preparing bronopol, which process comprises charging a reaction vessel with water, bromopicrin, nitromethane and paraformaldehyde, gradually feeding a base into said reaction vessel under stirring, bringing the reaction to completion and separating bronopol from the aqueous reaction mixture.
Abstract:
Process for the preparation of 1,1-cyclohexane-diacetic acid monoamide (CHDAAM), by amination of 1,1-Cyclohexane-diacetic anhydride (CDAAn) with aqueous ammonia, neutralization of the reaction mixture, such that crude CHDAAM is precipitated and filtered and by purification of the crude CHDAAM by crystallization from a solvent. The amination is carried out at a temperature kept below 20oC and with aqueous ammonia having a concentration from 25 to 35 wt%, in a molar ratio relative to the CHDAAn from 5 to 10. The neutralization is carried out with an aqueous solution of H2SO4 having a concentration from 30 to 70 wt% and is continued until a slightly acid solution is obtained.
Abstract:
A process, which comprises reducing 4-bromophthalic anhydride in an organic solvent, to obtain a mixture of 5-bromophthalide and 6-bromophthalide, acidifying the reaction mixture, separating the same into aqueous and organic phases, and selectively crystallizing 5-bromophthalide from the organic phase.
Abstract:
The invention relates to a process for preparing pentabromobenzyl acrylate through the reaction of pentahalobenzyl halide with a salt of acrylic acid in water-immiscible solvent, wherein said salt is in aqueous form and the reaction is carried out in the presence of a phase transfer catalyst. A process for polymerizing the pentabromobenzyl acrylate in halogenated aromatic solvent and the poly (pentabromobenzyl acrylate) obtained are also disclosed.
Abstract:
Process for the preparation of 1,1-cyclohexane-diacetic acid (CHDAA) from 1,5-dicarbonitrile-2,4-dioxo-3-azaspiro[5,5]undecane (the imide), by reacting it with sulfuric acid in two steps. The first step at a temperature lower than 100°C and the second step at a reaction temperature from 160 to 190°C. The first step is carried out by dissolving the imide in aqueous sulfuric acid at temperatures from about 65°to about 85°C and then cooling the solution thus obtained to room temperature. The second step is carried out by reacting said solution with aqueous sulfuric acid at temperatures of about 170°C.
Abstract:
The invention provides a process for preparing bronopol, which process comprises charging a reaction vessel with water, bromopicrin, nitromethane and paraformaldehyde, gradually feeding a base into said reaction vessel under stirring, bringing the reaction to completion and separating bronopol from the aqueous reaction mixture.
Abstract:
The invention provides a process for preparing bronopol, which process comprises charging a reaction vessel with water, bromopicrin, nitromethane and paraformaldehyde, gradually feeding a base into said reaction vessel under stirring, bringing the reaction to completion and separating bronopol from the aqueous reaction mixture.
Abstract:
The invention relates to a process for preparing pentabromobenzyl acrylate through the reaction of pentahalobenzyl halide with a salt of acrylic acid in water-immiscible solvent, wherein said salt is in aqueous form and the reaction is carried out in the presence of a phase transfer catalyst. A process for polymerizing the pentabromobenzyl acrylate in halogenated aromatic solvent and the poly (pentabromobenzyl acrylate) obtained are also disclosed.