A Practical Oxidative Conversion of Aldehydes into N-Chloroaldimines

A novel method for the preparation of N-chloroaldimines from commonly available aromatic aldehydes has been developed. The reaction proceeded effectively by two steps: aldehydes were initially transformed into imines and then chloro-substitution with NaClO2 gave the N-chloroaldimines. This simple protocol allows for the preparation of a variety of aromatic N-chloroaldimines in moderate to excellent yields without the isolation of the imine intermediate. We also found that 3-nitrobenzaldehyde and 4-cyanobenzaldehyde were converted into the related benzonitrile directly under the standard conditions.