Phosphazenium salt phase transfer catalysts
AssigneeGeneral Electric Company
InventorDaniel Brunelle
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Abstract
A method for carrying out a chemical reaction between at least two reactants occupying separate phases within a multiphase reaction mixture has been discovered in which at least one phosphazenium salt is employed as a phase transfer catalyst. The remarkable utility of phosphazenium salts as phase transfer catalysts is illustrated by the preparation of aromatic ethers. The phosphazenium salt phase transfer catalysts are shown to be especially useful in the preparation of aromatic polyethers such as polyether sulfones.
Claims27
A method for carrying out a chemical reaction between at least two reactants occupying separate phases within a multiphase reaction mixture, said reaction mixture comprising at least one phosphazenium salt phase transfer catalyst.
A method for making aromatic ethers comprising contacting in a reaction mixture the salt of at least one aromatic hydroxy compound with at least one aromatic compound comprising at least one leaving group, said contacting being carried out in the presence of a phosphazenium salt.
A method for making an aromatic polyether composition, said method comprising contacting in a reaction mixture the salt of at least one aromatic dihydroxy compound with at least one aromatic compound bearing at least two leaving groups, said contacting being carried out in the presence of a phosphazenium salt having structure I
- wherein n is an integer from zero to about 10, R1 and R2 are independently selected from the group consisting of C1-C20 aliphatic radicals, C3-C20 cycloaliphatic radicals, and C4-C20 aromatic radicals, and wherein said R1 and R2 may be linked together form a cyclic structure comprising at least one nitrogen atom, and wherein X− is selected from the group consisting of monovalent inorganic anions, monovalent organic anions, polyvalent inorganic anions, polyvalent organic anions, and mixtures thereof.
A method for making an aromatic polyether sulfone, said method comprising contacting in a reaction mixture the disodium salt of bisphenol A with bis(4-chlorophenyl)sulfone, said contacting being carried out in the presence of a phosphazenium salt having structure I
- wherein n is an integer from zero to about 10, R1 and R2 are independently selected from the group consisting of C1-C20 aliphatic radicals, C3-C20 cycloaliphatic radicals, and C4-C20 aromatic radicals, and wherein said R1 and R2 may be linked together form a cyclic structure comprising at least one nitrogen atom, and wherein X− is selected from the group consisting of monovalent inorganic anions, monovalent organic anions, polyvalent inorganic anions, polyvalent organic anions, and mixtures thereof, said contacting being carried out at a temperature in a range between about 200° C. and about 250° C., said contacting being carried out in the presence of orthodichlorobenzene.
Dependencies are inferred from the claim text.