59386-97-9Relevant articles and documents
New gas-phase domino processes leading to benzopyranones and benzofurans
Aitken, R. Alan,Chang, Da
, p. 164 - 184 (2017/03/11)
A new domino approach to flavones by gas phase pyrolysis of β,γ-dioxophosphonium ylides containing a 2-methoxyphenyl group is frustrated by unexpected and novel decarbonylation of the intermediate flavon-3-yl radical leading to 2-phenylbenzofuran. Alternative approaches based on dioxolane protection of one carbonyl, or selective elimination in β,β′-dioxo or β-oxo-β′-thioxo ylides were not successful, but pyrolysis of a β-oxo-β′-phenylimino ylide did give the required domino reaction leading to a protected benzopyranone in moderate yield.