Photo-induced aromatic assembly of benzocycloalka[1,2-b] furan and spiro[furan-2(3H),1′-benzocycloalkane] derivatives
摘要:
The photo-induced benzannulation of benzocycloalka[1,2-b]furans produced hydrohelicene-type compounds ill good yields. A similar photoreaction of the spiro[furan-2(3H),1'-benzocycloalkane]s afforded dihydrophenalene derivatives in moderate yields. Benzo[kl]xanthene was also formed by a similar photoreaction of spiro[furan-2(3H),9'-xanthene]. The reaction pathway was elucidated by the H-1 NMR spectrum of the reaction mixture and the alternative synthesis of the intermediate. (c) 2005 Elsevier Ltd. All rights reserved.
One-Pot Synthesis of Spirofuran and Benzocycloalka[1,2-<i>b</i>]furan Derivatives Using Manganese(III)-Mediated Oxidative Radical Cyclization
作者:Hiroshi Nishino、Reika Fujino
DOI:10.1055/s-2005-861807
日期:——
obtained by the oxidation of methylenebenzocycloalkanes with manganese(III) acetate in the presence of 1,3-dicarbonyl compounds. A similar oxidation of the benzocycloalkene derivatives produced the functionalized benzocycloalka[1,2-b]furans in good yields. However, l-benzyl-3,4-dihydronaphthalene gave both the corresponding spirofuran and benzocyclohexa[1,2-b]furan under the same oxidation conditions.