The Gomberg-type dimerization of bifluorenylidene radicals: an X-ray crystallographic investigation
作者:Laura E. Harrington、James F. Britten、Michael J. McGlinchey
DOI:10.1016/j.tetlet.2003.09.050
日期:2003.10
The reaction of phenylethynyllithium with 9-bromofluorene yields 9,9′-bifluorenylidene, 8, 9,9′-bifluorenyl, 9, and a molecule 10, of formula C52H32, in which coupling has occurred between a 9,9′-bifluorenyl fragment and a 9,9′-bifluorenylidene moiety such that a C(9) position of the former is attached to a C(3) site of the latter. This parallels the unsymmetrical radical coupling of triphenylmethyl
phenylethynyllithium与9-溴芴收率9,9'- bifluorenylidene,反应8,9,9'- bifluorenyl,9,和一个分子10,式C 52 H ^ 32,在其中有一个9,9'之间发生耦合-双芴基片段和9,9'-联芴基亚基部分,使得前者的C(9)位置与后者的C(3)位相连。这与三苯基甲基自由基的不对称自由基偶联作用平行,这导致了Gomberg二聚体,而不是六苯基乙烷。X射线晶体学已阐明了10的结构,并提供了机械原理。
Silylium‐Catalyzed Alkynylation and Etherification Reactions of Benzylic Acetates
作者:Belén Rubial、Alfredo Ballesteros、José M. González
DOI:10.1002/ejoc.202200051
日期:2022.7.14
Bistriflimide-catalyzed coupling reactions of benzylacetates with both trimethyl(alkynyl)silanes and trimethyl(alkoxy)silanes lead to propargyl arenes and benzyl alkyl ethers, respectively. The acid assists the release of the reactive trimethylsilylium ion into the media, which is the ultimate catalytic species. The cationic nature of the processes is documented.
Dimerization of 9-Phenylethynylfluorene to Di-indeno-naphthacene and Dispiro-[fluorene-dihydronaphthacene- fluorene]: An X-ray Crystallographic and NMR Study
作者:Laura E. Harrington、James F. Britten、Michael J. McGlinchey
DOI:10.1021/ol049967o
日期:2004.3.1
oxidation then yields a peroxide. A dihydronaphthacene bearing fluorenyl moieties spiro-bonded at the C(5) and C(11) positions was also identified. The structures of the naphthacenes were elucidated by X-ray crystallography, and a mechanistic rationale is offered. [reaction: see text]