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 | Regular issue | Vol 81, No. 2, 2010, pp.329-347
Published online, 1st December, 2009
DOI: 10.3987/COM-09-11860
Cyclization of 5-Cyano-6-cyanoimino-3,4-dihydropyridin-2(1H)-ones with Amines

Núria Mont, Francisco Carrión, José I. Borrell,* and Jordi Teixidó

*Molecular Engineering Group, IQS, Ramon Llull University, Via Augusta 390, E-08017 Barcelona, Spain


The cyclization of 5-cyano-6-cyanoimino-3,4-dihydropyridin- 2(1H)-ones with amines, leading to pyrido[2,3-d]pyrimidines, is studied. Four factors play an important role on the direction of cyclization: (1) the planarity of the reaction area; (2) the cyclization proceeds by the nucleophilic attack of an amidine onto an electrophilic group which can be either a cyano group or an alkylamidine; (3) the basicity of the amine plays an important role, the ionization of the substrate making more difficult the formation of the aforementioned amidine which is needed for the cyclization; and (4) the nucleophilic attack and the tautomerization of the cyclization product are processes which can occur practically simultaneously, so that the electronic movement involved in the tautomerization process coincides with the one which happens in the nucleophilic attack, both processes promoting each other.