Chinese Journal of Chemistry
© SIOC, CAS, Shanghai & WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Cover Picture: Synthesis of Two Coumarins Isolated from Aster praealtus (Chin. J. Chem. 7/2015)
The cover picture shows the first examples for the synthesis of coumarins via direct couplings of alcohols with C-7 coumarin halides. Such reactions proved to be much more difficult than similar couplings with simple substituted phenyl halides, especially when the alcohols are sterically congested as encountered in this work. En route to the first synthesis of the two long-known naturally occurring coumarins, several broadly employed coupling protocols were examined for the given substrates without success. In the end, the desired products were obtained by performing the reaction in xylene at 160°C in the presence of CuI/Cs2CO3/1,11-penanthroline. More details are discussed in the article by Wu and Liu et al. on page 723–728.