Base-promoted 1,6-conjugate addition of alkylazaarenes to para-quinone methides

Abstract

1,1,2-Triarylethanes embedded with an azaarene unit were prepared in a single step at ambient temperature via the sodium hexamethyldisilazide mediated 1,6-conjugate addition of unactivated alkylazaarenes on para-quinone methides (p-QMs). The extent of this methodology was investigated with a wide range of p-QMs and alkylazaarenes, and the respective products were obtained in moderate to excellent yields. The regioselective 1,6-conjugate addition of the trialkylazaarene precursor on para-quinone methide was also presented. Besides, we showcased the direct synthesis of the 1,1,2-triarylethane derivative from aldehyde via the in situ generation of para-quinone methide.