High-pressure cycloaddition reactions of 3-bromo-1,5-azulenequinone and 3-bromo-1,7-azulenequinone with dienophiles

Abstract

The high-pressure Diels–Alder reaction of 3-bromo-1,5-azulenequinone and 3-bromo-1,7-azulenequinone with several dienophiles under 300 MPa pressure gave 1∶1 [4 + 2] cycloadducts in good yields. Bromoazulenequinones reacted with dienophiles on the seven-membered ring in such a way as not to produce a cyclopentadienone moiety.

References

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