Several observers3 have reported the fact that a substituent in one ring of an aromatic ether, such as diphenyl ether, has a marked effect in both rings. Thus in 4-nitrophenyl phenyl ether the substitution of bromine in the 4-nitrophenyl radical is almost precluded and occurs only slowly in the unnitrated nucleus. On the other hand 4-methoxyphenyl phenyl ether undergoes bromination in the unsubstituted phenyl group at a rate which is even faster ...
