Synthese d'heterocycles bore-azote-carbone. Structure cristallographique du dimethyl-2,4 o-tolyl-3 methyl-8 dibora-2,4 diazaro-1,3 naphtalene

Article abstract of DOI:10.1016/0022-328X(91)83114-J

The reaction of anilines o-YC6H4NH2 (Y = H, F, Cl, Br, Me) with boron trihalides BX3 (X = F, Cl, Br, I) has been investigated.With BF3, only borazine derivatives (o-YC6H4NBX)3 (X = F) could be obtained, whereas BI3 mainly gives heterocycles related to diboradiazaronaphthalene (o-YC6H4NBX)2 (X = I).The steric bulk of Y has been shown to play an important role in obtaining these boron-nitrogen-carbon heterocycles.After methylation (X = Me), all these derivatives have been characterised by NMR spectroscopy.The crystal structure of 2,4-dimethyl-3-o-tolyl-8-methyl-2,4-dibora-1,3-diazaronaphthalene has been determined.A slight puckering of the diboradiazaronaphthalene part of the molecule is observed, which results in a boat conformation for the mineral part of this heterocycle and a reduced conjugation with the adjacent benzene ring.