Halogenated cinnamic acids and esters thereof, processes for the preparation thereof and halogenated aryldiazonium salts

US5516932A · kind A · utility

Assignee

• Hoechst GmbH · DE

Inventors

• Matthias Beller · Ostseebad Nienhagen, DE
• Hartmut Fischer · Hofheim, DE
• Laurent Weisse · Oberursel, DE
• Klaus Forstinger · Kelsterbach, DE
• Ralf Pfirmann · Griesheim, DE
• Heinz Strutz · Usingen, DE

Key dates

• Filing date: Jan 6, 1994
• Grant date: May 14, 1996
• Expiry date: Jan 6, 2014

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07C69/65
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

The present invention relates to compounds of the formula ##STR1## in which R.sup.1 and R.sup.2 are identical or different and are hydrogen or an alkyl radical having 1 to 18 carbon atoms and optionally containing oxygen, nitrogen or halogen, the radicals X, Y and Z are identical and are a fluorine, bromine or iodine atom or if two of the radicals X, Y or Z are identical or all of the radicals X, Y, Z are different from each other, X, Y and Z are a fluorine, chlorine, bromine or iodine atom. The invention further relates to a process for the preparation of the compounds, by reacting an aryldiazonium salt of the formula ##STR2## in which the radicals X, Y and Z are identical and are a fluorine, bromine or iodine atom or, if two of the radicals X, Y and Z are identical or all of the radicals X, Y, Z are different from each other, X, Y and Z are a fluorine, chlorine, bromine or iodine atom and A.sup.(-) is an anion of an acid having a pK.sub.a <7, with a compound of the formula ##STR3## in which R.sup.1 and R.sup.2 are identical or different and are hydrogen or an alkyl radical having 1 to 18 carbon atoms and optionally containing oxygen, nitrogen or halogen, in the presence of a pall…