Abstract
In 1876 W. F. Koppeschaar described first the quantitative bromination of phenol by acid-bromide-brom-ate solution. Ever since many chemists have investigated this method on the general assumption that bromine will replace quantitatively only those hydrogen atoms ortho or para to the hydroxyl group of phenols, but discovered many exceptions of the assumption. Recently Koppeschaar's method has been applied to the intermediates of the phenolic resins. In the present paper, the progress of the method during one century is mentioned, introducing the articles written by L. V. Redman, A. J. Weith, F. P. Brock (1913), A. R. Day, W. T. Taggart (1928), M. M. Sprung (1941), I. W. Ruderman (1946) and S. Seto, H. Horiuchi (1953). The present author pointed out that the polymethylolphenols will polymerise in the middle of the experiment and then the bromine value becomes a little smaller than the theoretical value.
