1999 Volume 48 Issue 5 Pages 463-470,505
After an ether solution of N-chloroacetanilide (1) and iron (III) chloride-hydrogen chloride complex (FeCl3-HCl) had stood at room temperature, the reaction was noted to have proceeded essentially to completion within 0.5h, and o- (10) and p-chloroacetanilide (11) were obtained as rearrangement products in various ortho-para ratios (10/11), depending on the particular concentration of FeCl3-HCl. The corresponding o- and p-chloroacetanilides were also produced by reaction of N-chloro-2-methylacetanilide with FeCl3-HCl. Two o-chloroacetanilides and a p-chloroacetanilide were obtained from N-chloro-3-methylacetanilide under the same reaction conditions. Some N-chloroacetanilides having chlorine in the parent aromatic nucleus failed to undergo Orton rearrangement under any conditions or; so that the corresponding acetanilides were obtained in lower yields. The rearrangement products, o- and p-chloroacylanilides, were obtained from N-chloro-2-methylpropionylanilide and N-chloro-2-methylbutyrylanilide under the same conditions.
