Z,Z-Tribenzo[c,g,k]cyclododecapentaene- 1,2-dione affords two crystalline forms that differ in conformation, which is revealed by X-ray crystallography. Dynamic conformational behavior in solution was studied by NMR spectroscopy. (C) 1999 Elsevier Science Ltd. All rights reserved.
Highly Active Palladium Catalyst for the Sonogashira Coupling Reaction of Unreactive Aryl Chlorides
作者:Dong-Hwan Lee、Young-Jun Kwon、Myung-Jong Jin
DOI:10.1002/adsc.201100747
日期:2011.11
communication reports on the β-diketiminatophosphane palladium-catalyzed copper-free Sonogashira coupling of arylchlorides with alkynes. A catalyst loading of 0.5 mol% is sufficient to achieve high performance under relatively mild reaction conditions. Furthermore, dialkynylbenzenes are efficiently prepared by one-pot double Sonogashira couplings of aryl dichlorides.
all-Z-tribenzo[12]annulene. Dehydrogenation of the anti-trimer with DDQ resulted in the formation of an indenoazulene derivative, and a similar reaction of the syn-trimer yielded a bowl-shaped system. All-Z-tribenzo[12]annulene was also synthesized using a stepwise route starting from o-diiodobenzene and o-ethynylbenzyl alcohol, the overall yield being 22%. All-Z-tribenzo[12]annulene behaved like π-prismand