5024-70-4Relevant academic research and scientific papers
Carbanionic friedel-crafts equivalents. Regioselective directed Ortho and remote metalation-C-N cross coupling routes to acridones and dibenzo[b,f]azepinones
MacNeil, Stephen L.,Gray, Matthew,Gusev, Dmitry G.,Briggs, Laura E.,Snieckus, Victor
supporting information; experimental part, p. 9710 - 9719 (2009/04/07)
(Chemical Equation Presented) Carbanion-mediated general regioselective routes to acridones 4 (Table 2) and dibenzo[b,f]azepinones 20 (Table 4) are described. Buchwald-Hartwig C-N cross coupling of o-halo benzamides 1 with anilines 2 or 16, followed by simple N-methylation, dependably provides N-methyl diarylamines 3 (Table 1) and 18 (Table 3). Upon treatment with LDA, 3 and 18 are converted into acridones 4 and dibenzo[b,f]azepinones 20, respectively, in good to excellent yields with regioselectivity which depends upon the presence or absence of directed metalation groups (DMGs). Brief investigations as follows are described: the synthesis of desmethyl acridone 15 (Scheme 4), an attempt to effect a double-directed remote metalation sequence which leads only to a monocyclization product 13 (Scheme 3), and an analogous but nonregioselective route to a xanthone 22 and dibenzo[b,f]oxepinone 24 (Scheme 5). DFT calculations reveal low energy conformations for compounds 18b and 23 which account for product formation and indicate that the cyclization reactions are under kinetic control.
Intramolecular Anionic Friedel-Crafts Equivalents. A General Regiospecific Route to Substituted and Naturally Occurring Xanthen-9-ones
Familoni,Ionica, Ileana,Bower, Justin F.,Snieckus, Victor
, p. 1081 - 1083 (2007/10/03)
An LDA-induced regiospecific and general conversion of diaryl ether 2-carboxamides 4 into substituted xanthones 5, including natural products, 2-hydroxy-1-methoxyxanthone (8) and 6-deoxyjacareubin (14), is described.
