Patents Represented by Attorney, Agent or Law Firm McDonald, Hopkins, Burke & Haber LLC
  • Patent number: 6417407
    Abstract: A 2-bromo-4-chloro substituted phenol is prepared from a first composition of a substituted phenol and benzotrifluoride in a weight ratio to the substituted phenol of about 2 to about 4. Into the first composition is sparged about 1 to about 1.5 equivalents of chlorine gas, whereby the substituted phenol is chlorinated to form a 4-chloro substituted phenol. The first composition is cooled to precipitate the 4-chloro substituted phenol, which can be isolated by filtration. A second composition is formed of the 4-chloro substituted phenol, acetic acid in an weight ratio to the 4-chloro substituted phenol of about 1 to about 2, about 1 to about 2 equivalents of a salt of a strong base and a weak acid, and about 1 to about 5 equivalents of a brominating agent, whereby the 4-chloro substituted phenol is brominated to form a 2-bromo-4-chloro substituted phenol.
    Type: Grant
    Filed: February 10, 2000
    Date of Patent: July 9, 2002
    Assignee: Gabriel Performance Products, LLC
    Inventors: Bao-Guo Huang, Lawrence B. Fertel