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.
Department of Organic Chemistry, Southern Federal University , Zorge str. 7, 344090 Rostov-on-Don, Russian Federation.
Vladimir Y
VY
Mikshiev
Department of Organic Chemistry, Southern Federal University , Zorge str. 7, 344090 Rostov-on-Don, Russian Federation.
Alexander S
AS
Antonov
Department of Organic Chemistry, Southern Federal University , Zorge str. 7, 344090 Rostov-on-Don, Russian Federation.
Alexander F
AF
Pozharskii