201-65-0Relevant articles and documents
Palladium-Catalyzed Coupling of 2,2'-Dihalobiaryls with Metallated Cyclopentenes. An Easy Synthesis for SpiroFluorene>s
Katz, Thomas J.,Gilbert, Adam M.,Huttenloch, Monika E.,Min-Min, Gu,Brintzinger, Hans H.
, p. 3551 - 3554 (1993)
In the presence of palladium catalysts, one of the two carbons attached to halogen in 2,2'-diiodobiphenyl couples with unsaturated organometallics, after which the other adds to the newly incorporated double bond.Spirofluorene>s can be synthesized in this way.
Palladium-Catalyzed Formal [4 + 1] Annulation via Metal Carbene Migratory Insertion and C(sp2)-H Bond Functionalization
Xu, Shuai,Chen, Ri,Fu, Zihao,Zhou, Qi,Zhang, Yan,Wang, Jianbo
, p. 1993 - 1997 (2017/08/14)
A highly efficient and operationally simple palladium-catalyzed formal [4 + 1] annulation reaction has been developed. The reaction is featured by the formation of two different C-C bonds on a carbenic center. It represents a concise method for the synthesis of a wide range of polycyclic aromatic hydrocarbons (PAHs) and 1H-indenes with easily available (trimethylsilyl)diazomethane as the carbene source. Metal carbene migratory insertion and C(sp2)-H bond activation are proposed as the key steps in this transformation. The reaction further demonstrates the versatility of the carbene-based coupling in combination with various transition-metal-catalyzed transformations.
Joining the rings: The preparation of 2- and 3-indenyl-triptycenes, and curious related processes
Nikitin, Kirill,Mueller-Bunz, Helge,Ortin, Yannick,McGlinchey, Michael J.
, p. 1952 - 1960 (2008/02/10)
The indenyltriptycenes, 1 and 2, where the 3- or 2-indenyl, respectively, is attached at the 9-position of the triptycene, are attractive prototypes of molecular gearing systems that can also incorporate a brake. These molecules have been prepared from their respective indenylanthracenes, 3 and 4, by the [4 + 2] cycloaddition of benzyne to the anthracene fragment, and the rotational barriers about the indenyl-triptycenyl single bonds in 1 (12 kcal mol -1) and 2 (-1) have been measured. The precursor anthracenes, 3 and 4, were prepared by using palladium-catalysed coupling reactions. Unexpectedly, the Heck-type reaction of 9-bromoanthracene, 5, with indene leads to the formation of 3-indenylanthracene 3; moreover, this process is accompanied by a novel palladium-catalysed carbocyclisation reaction leading to the indenophenanthrylene 9. The addition of benzyne to 9-(3-indenyl)anthracene, 3, yields the corresponding indenyltriptycene, 1, and, surprisingly, the anthracenyl methano-bridged phenanthrene 16. It has been demonstrated that 2-arylindenes can act as 1,3-dienes in the [4 + 2] cycloadditions of benzyne. The products 2, 7a, 9 and 16 have been characterised by X-ray crystallography. The Royal Society of Chemistry.
