Selective para-cyanation of alkoxy- and benzyloxy-substituted benzenes with potassium ferricyanide promoted by copper(II) nitrate and iodine

Article abstract of DOI:10.1002/adsc.201200235

A simple method was developed for selective para-cyanation of alkoxy- and benzyloxy-substituted benzenes with 0.5 equivalents of potassium ferricyanide, 0.8 equivalants of copper(II) nitrate and 0.5 equivalents of iodine in acetonitrile. Among various phenyl carbon-hydrogen bonds, those at the para-position with regard to the alkoxy or benzyloxy groups were selectively cyanated in 20% to 87% yields (23 examples). The present method uses commercially available reagents, and can be performed on a ten gram-scale. Interestingly, methoxybenzene was cyanated in 32% yield in the absence of potassium ferricyanide, which suggests that the nitrile group of a part of the product is possibly from the solvent acetonitrile. Copyright