A facile synthesis of β-(4-azuleno[1,2-b]thienyl) α,β-unsaturated ketones

Abstract

The facile and novel synthesis of β-(4-azuleno[1,2-b]thienyl) α,β-unsaturated ketones 1 from 2-tropylio-3-(2-furyl)thiophenes 7 is reported; a mechanism involving a novel ring cyclization by intramolecular attack of the tropylium ion at the 2-position of the furan ring is postulated.

References

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