"N-acyliminium ion pool" as a heterodiene in [4 + 2] cycloaddition reaction
Seiji Suga1, Aiichiro Nagaki, Yamato Tsutsui
1Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Kyoto 606-8501, Japan. suga@sbchem.kyoto-u.ac.jp
Abstract:
[reaction: see text] An N-acyliminium ion pool was found to undergo cycloaddition reaction with a variety of dienophiles such as alkenes and alkynes. A concerted mechanism seems to be most likely for alkyl-substituted alkenes as suggested by the DFT calculations, whereas a stepwise mechanism plays the major role for aryl-substituted alkenes. It is also noteworthy that the present study demonstrates the potential of the combination of the cation pool method and the micromixing in both mechanistic and synthetic aspects.
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