direct insertion of alkenes into unstrained ring 2-aryl-1,3-indandiones is reported, which provides a one-carbon ring expansion strategy for the synthesis of 1,4-naphthoquinones. Entirely differing from the existing reports, the alkenes herein behave as C1 units to participate in annulation reactions. This transformation provides a facile route to access a class of highly functionalized 1,4-naphthoquinones
Copper-Catalyzed Intramolecular Oxidative 6-exo-trig Cyclization of 1,6-Enynes with H2O and O2
作者:Zhi-Qiang Wang、Wen-Wu Zhang、Lu-Bin Gong、Ri-Yuan Tang、Xu-Heng Yang、Yu Liu、Jin-Heng Li
DOI:10.1002/anie.201104082
日期:2011.9.12
The novel CuCl2‐catalyzed title reaction of enynes has been developed for synthesizing substituted naphthoquinones (see scheme; DMA=dimethylacetamide). The method represents the first example of a copper‐catalyzed enyne oxidative cyclization for constructing 1,4‐naphthoquinones by the incorporation of two oxygen atoms into the organic framework from molecular oxygen and water.