The synthesis of spiro bis-indanes by means of N-heterocyclic carbene (NHC) catalysis is reported. The dimerization of various o-formylchalcone substrates or their combination with phthaldialdehyde derivatives under the catalysis of thiazolium-derived carbenes afforded Stetter-aldol-Michael products and Stetter-aldol-aldol products, respectively. The use of poor Michael acceptors in conjunction with
Brønsted Acid-Catalyzed Straightforward Synthesis of Benzo[<i>b</i>]carbazoles from 2,3-Unsubstituted Indoles
作者:Anisley Suárez、Patricia García-García、Manuel A. Fernández-Rodríguez、Roberto Sanz
DOI:10.1002/adsc.201300868
日期:2014.2.10
AbstractDescribed is a general and efficient synthesis of valuable benzo[b]carbazoles by Brønsted acid‐catalyzed reactions between simple C‐2,C‐3‐unsubstituted indoles and ortho‐[α‐(hydroxy)benzyl]benzaldehyde acetals. Highly selective migration processes are involved as key steps in the overall cascade sequence that involves the one‐pot formation of two new bonds and a cycle in a regioselective fashion.magnified image