221692-50-8Relevant articles and documents
Construction of Hexahydrophenanthrenes By Rhodium(I)-Catalyzed Cycloisomerization of Benzylallene-Substituted Internal Alkynes through C?H Activation
Kawaguchi, Yasuaki,Yasuda, Shigeo,Mukai, Chisato
, p. 10473 - 10477 (2016)
The treatment of benzylallene-substituted internal alkynes with [RhCl(CO)2]2effects a novel cycloisomerization by C(sp2)?H bond activation to produce hexahydrophenanthrene derivatives. The reaction likely proceeds through consecutive formation of a rhodabicyclo[4.3.0] intermediate, σ-bond metathesis between the C(sp2)?H bond on the benzene ring and the C(sp2)?RhIIIbond, and isomerization between three σ-, π-, and σ-allylrhodium(III) species, which was proposed based on experiments with deuterated substrates.
Dual Gold Catalysis: Synthesis of Fluorene Derivatives from Diynes
Bucher, Janina,Wurm, Thomas,Taschinski, Svenja,Sachs, Eleni,Ascough, David,Rudolph, Matthias,Rominger, Frank,Hashmi, A. Stephen K.
supporting information, p. 225 - 233 (2017/02/05)
1,5-Diyne systems bearing one terminal and one benzyl- or allyl-substituted alkyne attached to an aromatic backbone were converted in the presence of a gold catalyst. In a dual gold-catalyzed process, gold vinylidenes are formed that selectively undergo formal CH insertion into the C(sp2)–H bond of the offered unsaturated systems. If H atoms are present in the propargylic position, a subsequent isomerization to the aromatic system takes place leading to 9H-fluorene and 11H-benzo[b]fluorene derivatives as final products. In the case of a quaternary carbon in the propargylic position no further aromatization is observed and 10H-benzo[b]fluorene derivatives are obtained in high yield. (Figure presented.).