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. 20, 2003
Filed:
May. 31, 2001
Mervin G. Wood, Poughquag, NY (US);
Deborah DeHessa, Poughkeepsie, NY (US);
Joseph Suhadolnik, Yorktown Heights, NY (US);
Andrew B. Naughton, Mobile, AL (US);
Jerome Sanders, Mobile, AL (US);
Jacqueline Lau, Jericho, NY (US);
Rong Xiong, Dobbs Ferry, NY (US);
Joseph Babiarz, Amawalk, NY (US);
Ciba Specialty Chemicals Corporation, Tarrytown, NY (US);
Abstract
Provided is a process for preparing 2H-benzotriazole UV absorbers containing a perfluoroalkyl moiety at the 5-position of the benzo ring, for example a trifluoromethyl group, which involves diazotizing the perfluoroalkyl substituted o-nitroaniline using concentrated sulfuric acid plus sodium nitrite or nitrosylsulfuric acid to form the corresponding monoazobenzene intermediate via the diazonium salt intermediate which is reduced to the corresponding 5-perfluoroalkyl substituted 2H-benzotriazole UV absorber compound by conventional reduction means. Also provided is a novel one-pot, multiphase reaction for the preparation of 2(2-nitrophenylazo) substituted phenols, which are precursors for 2H-benzotriazole UV absorbers.