Rhodium-Catalyzed Regiodivergent [3 + 2] and [5 + 2] Cycloadditions of Quinolinium Ylides with Alkynes
Min He1, Nuan Chen1, Jian Wang1,2
1School of Biotechnology and Health Sciences , Wuyi University , Jiangmen 529020 , P. R. China.
Abstract:
Rhodium-catalyzed regiodivergent [3 + 2] and [5 + 2] cycloadditions of quinolinium ylides with alkynes are reported, providing highly functionalized five-membered indolizine derivatives and seven-membered 1,4-oxazepine compounds, respectively, in moderate to excellent yields under mild reaction conditions. Importantly, quinolinium ylides are derived from donor-acceptor diazo compounds, and different types of donor-acceptor diazo compounds exhibit distinct selectivity and reactivity for the reactions. The [3 + 2] cycloadditions involve an unusual 1,3-ester migration process.
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