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:
Dec. 02, 1997
Filed:
Sep. 05, 1996
Hoechst AG, Frankfurt, DE;
Abstract
The invention relates to a process for preparing phosphorus-containing compounds of the formula I ##STR1## in which R.sup.1 and R.sup.2 are an alkyl radical having 1 to 8 carbon atoms, a cyclohexyl radical, a cyclopentyl radical, an aryl radical or a halogen-, alkyl- or alkoxy-substituted aryl radical, where R.sup.1 and R.sup.2 together with the phosphorus atom can also form a ring, n and m=0 or 1 and R.sup.3 and R.sup.4 are alkyl radicals having 1 to 4 carbon atoms or n=0, m=0 or 1 and R.sup.3 and R.sup.4 are H, by adding compounds of the formula II ##STR2## into dialkyl esters of fumaric acid or of maleic acid of the formula (III) or dialkyl esters of itaconic acid of the formula (IV) ##STR3## in which R.sup.3 and R.sup.4 have the meaning given above, and, optionally reacting an alkyl ester of a phosphorus-containing dicarboxylic acid of the formula (I), where n=0, with water in the presence of catalytic amounts of an acid to give the phosphorus-containing dicarboxylic acid.