Resources Contact Us Home
Browse by: INVENTOR PATENT HOLDER PATENT NUMBER DATE
 
 
Preparation of aromatic fluoro compounds
T993005 Preparation of aromatic fluoro compounds
Patent Drawings:

Inventor: Staniland
Date Issued: April 1, 1980
Application: 06/022,597
Filed: March 19, 1979
Inventors: Staniland; Philip A. (Tewin Wood, GB2)
Assignee: Imperial Chemical Industries Limited (London, GB2)
Primary Examiner:
Assistant Examiner:
Attorney Or Agent:
U.S. Class: 1/1
Field Of Search:
International Class:
U.S Patent Documents:
Foreign Patent Documents:
Other References:









Abstract: The present invention relates to a process for the preparation of 4,4'-difluorobenzophenone. 4,4-difluorobenzophenone may be prepared by diazotization of 4,4'-diamino-diphenylmethane in anhydrous or concentrated aqueous hydrogen fluoride, decomposition of the diazonium fluoride thus produced to yield 4,4'-difluoro-diphenylmethane and oxidation of 4,4'-difluoro-diphenylmethane to yield 4,4'-difluorobenzophonone.Thus, according to the present invention, there is provided a process for the preparation of 4,4'-difluorobenzophenone which comprises the following steps:(1) diazotization of 4,4'-diamino-diphenylmethane in anhydrous or concentrated aqueous hydrogen fluoride to yield a solution of a corresponding diazonium fluoride; and(2) (i) thermally decomposing the diazonium fluoride in the solution thus produced to yield 4,4'-difluoro-diphenylmethane and (ii) subsequently oxidizing the 4,4'-difluoro-diphenylmethane to yield 4,4'-difluorobenzophenone.
Claim:
Description:
 
 
  Recently Added Patents
Image forming apparatus
Systems and methods for selective text to speech synthesis
Liquid crystal display
Sporting goal practice screen
Method to dynamically tune precision resistance
System for highlighting targets on head up displays with near focus plane
Semiconductor apparatus
  Randomly Featured Patents
Electromagnetic valve
Drill pipe protector
Saw filter including multistrip coupler with varied widths
Process for controlling the position of fibrous webs
Data presentation system for abnormal situation prevention in a process plant
Embroidery data editor that displays usable embroidery frame
Rotative joint applicable in pneumatic air pressure control assembly
Binder locking ring mechanism with configured trigger
Position encoder employing three or more colors
Process for producing a polycarbonate in inert solvent