
%0 Journal Article
%A Haynes, RK 
%A Peters, JM 
%A Wilmot, ID 
%T Lewis-acid-catalysed reaction of oxygen with 1,3-diphenylisobenzofuran, tetraphenylfuran and tetraphenylcyclopentadiene
%J Australian Journal of Chemistry
%D 1980/12/01
%V 33
%N 12
%P 2653-2661
%K 
%R https://doi.org/10.1071/CH9802653
%U https://www.publish.csiro.au/paper/CH9802653 
%X 1,3-Diphenylisobenzofuran is converted into o-dibenzoylbenzene (40-70%) by oxygen, either in dichloromethane at -78&#176; in the presence of 1-2 equiv. of a variety of Lewis acids, or on silica gel at 20&#176;, in the dark. Tetraphenylfuran is converted into (Z)-dibenzoylstilbene (55-65%) under the former conditions in the presence of 0.05 equiv. of I2 or SnI4 under irradiation from a tungsten lamp. The conversions, which correspond to a mono-oxygenation process, do not involve as intermediates the furan endoperoxides, which were independently generated from the furans by use of singlet oxygen. 2,5-Dimethylfuran and p-menthofuran do not react with oxygen in the presence of Lewis acids under the foregoing conditions. Tetraphenylcyclopentadiene is converted by oxygen into the corresponding endoperoxide (70-85%) in the presence of 0.05 equiv. of I2 and SnI4 or 0.1 equiv. of Ph3C+BF4- in dichloromethane at -78&#176; under irradiation. 
