An organocatalytic method for the synthesis of some novel xanthene derivatives by the intramolecular Friedel–Crafts reaction
作者:Tülay Yıldız、Hatice Başpinar Küçük
DOI:10.1039/c6ra27094h
日期:——
An efficient organocatalytic method for the synthesis of new substituted 9-arylxanthenes (2a–2u) starting from diarylcarbinol compounds with an arenoxy group (1a–1u) has been developed using the intramolecular Friedel–Crafts reaction. The substrates were prepared in two steps by Ullmann-type coupling and then Grignard reaction. Some organic Brønsted acids were studied as catalysts (3a–3g) in the intramolecular
Rearrangement of 2-Aryloxybenzaldehydes to 2-Hydroxybenzophenones by Rhodium-Catalyzed Cleavage of Aryloxy CO Bonds
作者:Honghua Rao、Chao-Jun Li
DOI:10.1002/anie.201103599
日期:2011.9.12
Lost in the shuffle: An unprecedented rearrangement of the title compounds proceeds by the simultaneous rhodium‐catalyzed cleavage of aryloxy CO and aldehyde CH bonds (see scheme). The reaction tolerates the presence of various catalytically reactive substituents such as aryl halides, nitrile, and esters.
Rhodium-Catalyzed Xanthone Formation from 2-Aryloxybenzaldehydes via Cross-Dehydrogenative Coupling (CDC)
作者:Ping Wang、Honghua Rao、Ruimao Hua、Chao-Jun Li
DOI:10.1021/ol203381q
日期:2012.2.3
A concise and straightforward strategy to construct a xanthone skeleton via an intramolecular cross-dehydrogenative coupling (CDC) of 2-aryloxybenzaldehydes has been developed. The reaction proceeded smoothly without any need of preactivation of the aldehyde group. It can tolerate various functional groups and provides an applicable protocol to construct a wide range of xanthone derivatives.