Nitration reactions with acid anhydride promoters
AssigneeGeneral Electric Company
InventorRoy R. Odle
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Abstract
An improved all nitric acid nitration process for the nitration of phthalic acid, phthalic anhydrides and derivatives thereof wherein the improvement consists essentially of employing a rate enhancing amount of a nitration promoting inorganic acid anhydride to enhance the rate of nitration.
Claims15
An improved process for the nitration of a phthalic acid substrate, comprising (1) forming a solution of the phthalic acid substrate selected from the group consisting of phthalic acid, phthalic anhydride, halo and C.sub.1 to C.sub.10 alkyl substituted derivatives of either and diacid, dianhydride, acid anhydide and acid halide functional derivatives of the foregoing in a solvent consisting essentially of nitric acid of at least about 95% concentration, (2) reacting the mixture within a temperature range of from about -20.degree. C. to about the boiling point of nitric acid, (3) allowing the nitration reaction to run to produce the nitrated derivatives of the phthalic acid substrate and (4) thereafter recovering the nitrated derivatives by methods known in the art, wherein the improvement consists essentially of adding an effective rate-enhancing amount of a nitration-promoting inorganic acid anhydride to said phthalic acid substrate solution prior to initiation of the nitration reaction as a means of enhancing the rate of nitration.
An improved process for the nitration of phthalic anhydride and halo and C.sub.1 to C.sub.10 alkyl substituted derivatives thereof comprising (1) forming a solution of the phthalic anhydride or derivative thereof in a solvent consisting essentially of at least about 95% nitric acid, (2) reacting the mixture within a temperature range of from about -20.degree. C. to the boiling point of nitric acid, (3) allowing the nitration reaction to run to produce the nitrated derivatives of the phthalic anhydride or derivative thereof and (4) thereafter recovering the nitrated derivatives by methods known in the art, wherein the improvement consists essentially of adding an effective rate-enhancing amount of a nitration-promoting inorganic acid anhydride to said solution of phthalic anhydride or derivative thereof prior to initiation of the nitration reaction as a means of enhancing the rate of nitration.
Dependencies are inferred from the claim text.