An improved synthetic process for 3-benzyloxy-4-n-butylaniline hydrochloride the key intermediate of nequinate which is an anticoccidal drug to parasites of Eimeria

was described.The process was started with 3-aminophenol

via acylation

Fries rearrangement

benzylation

hydrolysis

and Huang-Minlon reduction

to give the title compound.The optimal reaction conditions and molar yield were as follows: acylation

130—140℃ for 3 h; Fries rearrangement

140℃ for 5 h

77.9%(based on 3-aminophenol); benzylation

70℃ for 2 h and 80℃ for 4 h

81.3%; hydrolysis and Huang-Minlon reduction

reflux for 90 min

78.2%.The structures of the main compounds were confirmed by 1H NMR. The process is much of industrial value because of high yields

cheap and available materials

moderate reaction conditions and convenient operations.