Online article for Non-subscribers

Pay per view

Heterocycles has a pay-per-view service for Non-subscribers.
You will be able to directly purchase the full text article through PayPal.
Your purchased Paper can be downloaded after the payment is completed.
An e-mail will be sent the URL to download the paper.
If you have any questions, please contact:

Price: ¥ 4,400 (Yen only)
Period: This Article can be accessed for 7 days.

Communication | Regular issue | Vol 36, No. 8, 1993, pp.1725-1728
Published online, 1st January, 1970
DOI: 10.3987/COM-93-6397
Synthesis of Methyl 2-Cyano-(1,2-dimethylcyclohepta[b]pyrrol-6-ylidene)acetate. A Steric Effect to Accelerate the Geometrical Isomerism of the Exocyclic C=C Bond of Heterocycle-fused Heptafulvenes

Yukari Ikeda, Bing Zhu Yin, Nobuo Kato, Akira Mori,* and Hitoshi Takeshita*

*Instituete of Advanced Material Study, Kyushu University, 6-1, Kasuga-koen, Kasuga 816-8580, Japan


The rotational barriers of the exocyclic C=C bonds of heptafulvenes condensed with furan, pyrrole, and thiophene rings were largely dependent on the steric repulsion around the exocyclic C=C bonds; newly synthesized methyl 2-cyano-(1,2-dimethylcyclohepta[b]pyrrol-6-ylidene)acetate and its furanylidene analogue revealed higher energy barriers than the corresponding methyl 2-cyano-(1,2-dimethylcyclohepta[b]pyrrol-8-ylidene)acetate and the furan derivatives.