Process for preparing bromine- and fluorine-containing halogenated hydrocarbons

US4222967A · kind A · utility

Assignee

• Kali-Chemie Aktiengesellschaft · DE

Inventors

• Horst Boehm · Frankfurt am Main, DE
• Karl Hellberg · Hannover, DE

Key dates

• Filing date: Jun 27, 1977
• Grant date: Sep 16, 1980
• Expiry date: Jun 27, 1997

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02P20/582
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

A process for brominating fluorine- and chlorine-containing halogenated hydrocarbons of formula (I) ##STR1## wherein R.sub.1 represents hydrogen, fluorine, chlorine, bromine, lower alkyl, or at least partially fluorinated lower alkyl; R.sub.2 represents hydrogen, fluorine, chlorine, or bromine; and, R.sub.3 represents fluorine or perfluorinated lower alkyl, to form the corresponding compounds of formula (II) ##STR2## wherein R.sub.1, R.sub.2 and R.sub.3 are as defined above is disclosed. According to this process, compounds of formula (I) are reacted in gaseous form at relatively mild reaction conditions, e.g., reaction temperatures of between 100.degree.-500.degree. C. with hydrogen bromide in the presence of a catalyst comprising at least one component selected from the group consisting of PA1 (a) active carbon, PA1 (b) silica gel, PA1 (c) active alumina, and PA1 (d) a bromide of an element selected from the group consisting of Li, Na, K, Rb, Cs, Mg, Ca, Sr, Ba, Zn, Cd, Cu, Ag, Al, Tl(I), Pb, Cr, Mn, Fe, Co, Ni, rare earth metals and metals of the platinum group.