The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 06, 2009
Filed:
Jul. 08, 2004
Mark Wehner, Niedernhausen, DE;
Bettina Kirschbaum, Turnhout, BE;
Lothar Deutscher, Schwalbach, DE;
Hans Jürgen Wagner, Hattersheim, DE;
Harald Hössl, Kelkheim, DE;
Mark Wehner, Niedernhausen, DE;
Bettina Kirschbaum, Turnhout, BE;
Lothar Deutscher, Schwalbach, DE;
Hans Jürgen Wagner, Hattersheim, DE;
Harald Hössl, Kelkheim, DE;
Archimica GmbH, Frankurt am Main, DE;
Abstract
Disclosed is a method for producing cyclic phosphonic acid anhydrides of formula (III) by a) reacting phosphonic acid derivatives of formula (I) with acetic anhydride at a temperature ranging between 30 and 150° C. while separating a mixture of ethanoic acid and acetic anhydride by means of distillation, b) then reactively distilling the oligomeric phosphonic acid anhydrides of formula (II) obtained in step a) and transforming the same into the corresponding cyclic trimeric phosphonic acid anhydrides of formula (III), wherein n represents a number between 0 and 300 while R represents allyl, aryl, or open-chain, cyclic, or branched Cto Calkyl radicals, aryloxy, allyloxy, or alkoxy comprising open-chain, cyclic, or branched Cto Calkyl radicals. Preferably the cyclic trimeric phosphonic acid anhydrides formed in step b) are immediately dissolved in an organic solvent that exhibits an inert behavior relative thereto.