Tandem Synthesis of 10-Dimethylaminobenzo[h]quinazolines from 2‑Ketimino-1,8-bis(dimethylamino)naphthalenes via Nucleophilic Replacement of the Unactivated Aromatic NMe2 Group

It has been found that 2-bromo-1,8-bis­(dimethylamino)­naphthalene on sequential treatment with n-BuLi and 2 equiv of the same or different aryl­(hetaryl) cyanide as a result of [2 + 2 + 2] nucleophilic cascade annulation produces 10-dimethylaminobenzo­[h]­quinazolines, as yet unknown NMe2/–N analogues of the proton sponge. It is even more convenient to use preliminarily prepared 2-ketimino-1,8-bis­(dimethylamino)­naphthalenes as starting material. The substitution of both peri-NMe2 groups furnishing quinazolino­[7,8-h]­quinazoline derivatives is also possible. The process is remarkable by surprisingly mild nucleophilic displacement of an unactivated aromatic NMe2 group.