Patent ID: 6417407
Filing Date: 2002-07-09
Classification: C07C

Abstract:
A method of making a 2-bromo4-chloro substituted phenol having the general formula comprising(A) preparing a first composition which comprises (1) a substituted phenol having the general formula â€ƒand (2) benzotrifluoride in a weight ratio to said substituted phenol of about 2 to about 4; (B) sparging into said first composition about 1 to about 1.5 equivalents of chlorine gas, whereby said substituted phenol is chlorinated to form a 4-chloro substituted phenol having the general formula (C) cooling said first composition to precipitate said 4-chloro substituted phenol; (D) isolating said 4-chloro substituted phenol; and (E) forming a second composition which comprises (1) said 4-chloro substituted phenol; (2) acetic acid in an weight ratio to said 4chloro substituted phenol of about 1 to about 5; (3) about 1 to about 2 equivalents of a salt of a strong base and a weak acid; and (4) about 1 to about 2 equivalents of a brominating agent, where R is CHO, COCl, or CO2Râ€³, Râ€³ is alkyl from C1 to C4, each Râ€² is independently selected from alkyl from C1 to C4, m is 0 or 1, and n is 0 or 1.