(4+2)-Cycloaddition Reactions of Ketenes; Pyranones

• Main Author: Agho, Michael O. (Michael Osarenogowu)
• Other Authors: Brady, William Thomas
• Format: Others
• Language: English
• Published: North Texas State University 1983
• Subjects: cycloaddition reactions; ketenes; pyranones; Ring formation (Chemistry); Ketenes.
• Online Access: https://digital.library.unt.edu/ark:/67531/metadc331498/

This study deals with the (4+2)-cycloaddition reactions of 4-π electron compounds with ketenes. Chloroketenes were generated in situ from the corresponding chlorinated acid chlorides in the presence of the ketenophiles. Chloro-, dichloro- and diphenylketenes reacted with 1-methoxy-3-trimethylsiloxy-l,3-butadiene, and 2,4-bis(trimethylsiloxy)-1,3-pentadiene to yield the corresponding dihydropyrans. The dihydropyrans yielded substituted 4-pyranones on hydrolysis.