Aminoalkylation of electron-rich aromatic compounds using preformed iminium salts derived from aldehydes other than formaldehyde

Article abstract of DOI:10.1055/s-1996-4301

Preformed iminium salts derived from aldehydes other than formaldehyde are demonstrated to be excellent reagents for the aminoalkylation of indoles, phenols and N,N-dimethylaniline. This method provides a simple and straightforward route to a variety of aromatic Mannich bases which are difficult to obtain by other procedures. Surprisingly, the reaction between N-methylindole or 2-naphthol with a preformed N-silyl iminium salt led to the formation of a bisindolylmethane or a dihydrooxazine derivative, respectively.