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.

Paper | Special issue | Vol 54, No. 2, 2001, pp.667-678
Published online, 1st January, 1970
DOI: 10.3987/COM-00-S(I)41
Reaction of 2-Aminoazulenes with Aldehydes. One Pot Synthesis of Diazuleno[2,1-b:1,2-e]pyridines

Tetsuo Okujima, Tomomi Terazono, Shunji Ito,* Noboru Morita,* and Toyonobu Asao

*Department of Chemistry, Graduate School of Science, Tohoku University, Sendai 980-8578, Japan


Diazuleno[2,1-b:1,2-e]pyridines (2a and 2b) were prepared in one pot by the reaction of 2-aminoazulene (1a) with paraformaldehyde or benzaldehyde in moderate yields. Bis(2-amino-3-ethoxycarbonyl-1-azulenyl)methane (8a) was formed by the reaction of ethyl 2-aminoazulene-1-carboxylate (1b) with 1/2 molar amount of paraformaldehyde. Treatment of 8a with paraformaldehyde at room temperature afforded three heterocyclic compounds (9, 10, and 11). When 2-acetylaminoazulenes (1c and 1d) were used for this reaction, bis(2-acetylamino-1-azuleny)methanes (8b and 8c) were exclusively formed.