87682-42-6Relevant articles and documents
Cu/Pd-Catalyzed Cascade Reactions of Cyclic Diaryliodoniums and Alkynes - Access to Fluorenes with Conjugate Enynes/Dienes
Liu, Zhenquan,Luo, Bingling,Liu, Xiaomin,Hu, Yumim,Wu, Baojian,Huang, Peng,Wen, Shijun
, p. 1110 - 1118 (2016/03/05)
Unlike the widely studied linear diaryliodoniums as electrophilic arylating reagents, cyclic diaryliodoniums have the potential to initiate dual arylations with atom and step economy. In our current work, cascade reactions of cyclic diaryliodoniums and two equivalent alkynes have been successfully achieved under mild conditions, catalyzed by CuI/PdCl2(PPh3)2. The transformation could also be realized in a stepwise way with two different alkynes or with one alkyne and one alkene. The reaction enables a rapid access to a variety of complex fluorenes containing conjugate enyne and diene fragments. The Cu/Pd-catalyzed cascade reactions of cyclic diaryliodoniums and alkynes enable the facile construction of structurally diverse fluorenes with conjugate enynes/dines in one or two steps.
Anomaly in Palladium-Catalyzed Phenylethynylation of 2,2'-Dihalobiphenyls: Formation of Alkylidenefluorenes
Dougherty, T. Kirk,Lau, Kreisler S. Y.,Hedberg, Frederick L.
, p. 5273 - 5280 (2007/10/02)
2,2'-Diiodobiphenyl and 5,5'-dinitro-2,2'-dihalobiphenyls underwent palladium-catalyzed phenylethynylation with 2 mol of phenylacetylene to yield 3-(fluoren-9-ylidene)-1,3-diphenylpropyne and 3-(3,6-dinitrofluoren-9-ylidene)-1,3-diphenylpropyne, respectively.These fluorenyl compounds exhibited well-defined splitting patterns for the fluorenyl ring protons in the 250-MHz proton NMR spectra.The structure of 3-(fluoren-9-ylidene)-1,3-diphenylpropyne was further confirmed by an independent synthesis via the thermolysis of diethyl 3-(fluoren-9-ylidene)-1,3-diphenylpropen-1-yl phosphate.The mechanistic importance of the complex iodo(fluoren-9-ylidenebenzyl)bis(triphenylphosphine)palladium(II) in the catalytic cycle was established on the basis of its reaction with phenylacetylene to give 3-(fluoren-9-ylidene)-1,3-diphenylpropyne.
