37567-80-9Relevant articles and documents
A concise approach to anthraquinone-xanthone heterodimers
Holmbo, Stephen D.,Pronin, Sergey V.
, p. 5065 - 5068 (2018/04/24)
A synthetic approach to anthraquinone-xanthone heterodimers is described. The route to the pentacyclic core features an efficient assembly of a benzocycloheptenone via a new intramolecular oxidative arylation of an enol ether and a Hauser-Kraus annulation-aldol reaction sequence to access the characteristic bicyclo[3.2.2]nonene motif. Acremoxanthone A is synthesized in 10 steps from commercially available material to demonstrate the application of this approach.
Radical-mediated cyclisation of ω-aryl-β-dicarbonyl compounds to tetrahydrobenzocyclohepten-6-ones, hexahydrobenzocycloocten-6-ones and naphthalen-2(1H)-ones
Jamie, Joanne F.,Rickards, Rodney W.
, p. 3613 - 3621 (2007/10/03)
Manganese(III) acetate in acetic acid promotes efficient radical-mediated oxidative cyclisation of ε-aryl-β-dicarbonyl and Z-γ,δ-unsaturated δ-aryl-β-dicarbonyl compounds carrying electron-releasing groups in the aromatic ring, forming 6,7,8,9-tetrahydro-5H-benzocyclohepten-6-ones and naphthalen-2(1H)-ones, respectively. The process is accompanied by secondary acetoxylation at the activated benzylic position of the initial cyclisation products, and is exemplified by the conversions of the ε- and δ-aryl-β-dicarbonyl compounds 6 and 11 into the benzocycloheptenone 18 and the naphthalenone 21, respectively. Application of the oxidation to the formation of 8-membered hexahydro- and tetrahydro-benzocycloocten-6-ones 19 and 22 from ζ-aryl-β-dicarbonyl and Z-γ,δ-unsaturated ζ-aryl-β-dicarbonyl compounds is limited by low reactivity, and in the latter case, by radical rearrangement followed by cyclisation to a tetralin.
