
%0 Journal Article
%A Banwell, Martin G. 
%A Clark, George R. 
%A Hockless, David C. R. 
%A Pallich, Susanne 
%T Model Studies Directed Towards the Synthesis of the Oxetane D-Ring of Paclitaxel: Assessment of the Oxyanion-Assisted Retro-Diels-Alder Reaction as a Means for Generating Oxete
%J Australian Journal of Chemistry
%D 2002/04/04
%V 54
%N 11
%P 691-704
%K 
%R https://doi.org/10.1071/CH01161
%U https://www.publish.csiro.au/paper/CH01161 
%X In connection with attempts to generate oxete (8) via anionically assisted retro-Diels&#8211;Alder reaction, the oxetanes (11) and (12) have been prepared together with their acyclic analogues (35) and (36). The X-ray crystal structure of compound (11) has been determined. Each of the substrates (11), (12), (35) and (36) was treated with potassium hydride in the presence of 18-crown-6, conditions known to promote retro-Diels&#8211;Alder reactions in other systems. However, the first three substrates failed to engage in any such reaction even at temperatures up to 100&#x02DA;C. In contrast, at 18&#x02DA;C compound (36) reacted to give anthrone (13) in quantitative yield. These results indicate, inter alia, that regioelectronic effects play a crucial role in determining the success, or otherwise, of anionically-assisted retro-Diels&#8211;Alder reactions leading to polarized alkenes. 
