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:
May. 17, 2005
Filed:
Feb. 03, 2003
Axel Klauck-jacobs, Whitehall, PA (US);
Kathryn Sue Hayes, Plymouth Meeting, PA (US);
Reiner Taege, Heiligenhaus, DE;
William Casteel, Emmaus, PA (US);
Gauri Sankar Lal, Whitehall, PA (US);
Axel Klauck-Jacobs, Whitehall, PA (US);
Kathryn Sue Hayes, Plymouth Meeting, PA (US);
Reiner Taege, Heiligenhaus, DE;
William Casteel, Emmaus, PA (US);
Gauri Sankar Lal, Whitehall, PA (US);
Air Products and Chemicals, Inc., Allentown, PA (US);
Abstract
A method of preparing vicinal difluoro aromatic compounds in high yield from hydroxy aromatic compounds using various bases and a method of preparing intermediates thereof. A method for making a vicinal difluoro halogenated aromatic compound including providing a tetrafluoro derivative of a halogen substituted aromatic compound, wherein the tetrafluoro derivative has two fluorine atoms on each of two adjacent carbons and at least one additional halogen substituent; reacting the tetrafluoro derivative with a reducing agent in presence of a base for a reaction time sufficient to form the vicinal difluoro halogenated aromatic compound containing two vicinal fluorine substituents and the at least one additional halogen substituent, wherein the reducing agent is used in a reducing agent effective amount sufficient to retain the at least one additional halogen substituent.