Obtention of Anthraquinones by Selective Oxidation of the Corresponding Anthracenes and 9,10-Dimethoxyanthracenes with Copper or Zinc Nitrate supported on Silica Gel
作者:Mario Anastasia、Pietro Allevi、Cristina Bettini、Alberto Fiecchi、Anna Maria Sanvito
DOI:10.1055/s-1990-27101
日期:——
Anthracene, 9,10-dimethoxyanthracene and substituted analogues are selectively oxidized to the corresponding anthraquinones in good yields by copper(II) or zinc(II) nitrate supported on silica gel; the ether groups at different position from 9 and 10 are unaffected.
The efficient total synthesis of (-)-balanol, a potent inhibitor of the protein kinase C, is described. (-)-Balanol consists,of a chiral hexahydroazepine-containing fragment and a benzophenone fragment, both of which were prepared via novel synthetic routes. The hexahydroazepine fragment was prepared in racemic form through either Bu3SnH- or SmI2-promoted radical cyclization of oxime ethers 2ab intramolecularly connected with the formyl group. SmI2-promoted radical cyclization of 2b was found to be particularly successful in the selective synthesis of the seven-membered trans-amino alcohol 8b. Preparation of the enantiomerically pure hexahydroazepine-containing fragment was achieved through the enantioselective enzymatic acetylation of racemic alcohol 9, employing the immobilized lipase from Pseudomonas sp. The benzophenone fragment was prepared in short steps through a biomimetic oxidative anthraquinone ring cleavage starting from commercially available natural chrysophanic acid 15c. This reaction proceeded via [4 + 2]-cycloaddition of singlet oxygen to anthracene derivative 17c, followed by Baeyer-Villiger-type rearrangement of the resulting hydroperoxide to afford the benzophenone derivatives 22 and 23.
Lepage, Annales de Chimie (Cachan, France), 1959, vol. <13> 4, p. 1137,1176
作者:Lepage
DOI:——
日期:——
Boniface, Peter J.; Cambie, Richard C.; Carroll, David R., Australian Journal of Chemistry, 1994, vol. 47, # 3, p. 441 - 450
作者:Boniface, Peter J.、Cambie, Richard C.、Carroll, David R.、Marsh, Nicholas F.、Milbank, Jared B. J.、et al.