RSS-Feed abonnieren
DOI: 10.1055/s-2006-955665
First Organocatalytic Asymmetric Biginelli Reaction
X.-H. Chen, X.-Y. Xu, H. Liu, L.-F. Cun, L.-Z. Gong*
University of Science and Technology of China, Hefei, Chengdu Institute of Organic Chemistry and , Graduate School of the Chinese Academy of Sciences, Beijing, P. R. of China
Publikationsverlauf
Publikationsdatum:
15. Dezember 2006 (online)
Significance
The first highly enantioselective organocatalytic Biginelli reaction is described. Starting from an aldehyde (1), thiourea, and various acetoacetates (2), this acid-catalyzed multicomponent reaction furnishes thio-analogues of diversely substituted 3,4-dihydropyrimidin-2-(1H)-ones (DHPMs) (3), in moderate to good yields and high enantioselectivities. As chiral Brønsted acid organocatalyst the authors employed a binol-derived phosphoric acid. Moreover, three examples of the use of urea instead of thiourea are shown to obtain original DHPMs rather than the thio-analogues. Furthermore, an application in the synthesis of the drug monastrol is reported.