18052-85-2Relevant articles and documents
Naphthalenes, isoquinolines, and a benzazocine from zirconocene - Copper-mediated coupling of benzocyclobutadiene with nitriles and alkynes
Ramakrishna,Sharp, Paul R.
, p. 877 - 879 (2003)
(Matrix presented) Commercially available 1-bromobenzocyclobutene is a potentially useful synthon particularly with the application of organometallic methodology. Here we show that it is readily converted into Cp 2Zr(benzocyclobutadiene), which couples with alkynes or nitriles giving five-membered zirconacycles. Treatment of these alkyne- or nitrile-derived zirconacycles with CuCl yields substituted naphthalenes, isoquinolines, or in the presence of MeO2C-CC-CO2Me, a 2-benzazocine containing an eight-membered ring.
Nickel-Catalyzed Decarbonylation of Acylsilanes
Ito, Yuri,Kodama, Takuya,Nakatani, Syun,Sakurai, Shun,Tobisu, Mamoru
, p. 7588 - 7594 (2020/06/27)
Nickel-catalyzed decarbonylation of acylsilanes is developed. In sharp contrast to cross-coupling reactions of acylsilanes, in which the silyl group serves as a leaving group, the silyl group is retained in the product in this decarbonylation reaction. Although the strong binding of the dissociated CO to the nickel center frequently hinders catalyst turnover in nickel-mediated decarbonylative reactions, this reaction can be catalyzed by nickel complexes bearing a CO ligand.
Silyloxyarenes as Versatile Coupling Substrates Enabled by Nickel-Catalyzed C-O Bond Cleavage
Wiensch, Eric M.,Todd, David P.,Montgomery, John
, p. 5568 - 5571 (2017/09/15)
Silyloxyarenes are demonstrated to be a versatile substrate class in a variety of nickel-catalyzed coupling processes. The C(sp2)-O bond of aryl silyl ethers is directly transformed into C-H or C-Si bonds using Ti(O-i-Pr)4 or trialkylsilanes as reagents using nickel catalysts with N-heterocyclic carbene (NHC) ligands. Paired with the useful characteristics of silyl protecting groups, these methods enable protected hydroxyls to directly participate in high-value bond-forming steps rather than requiring deprotection-activation strategies that conventional approaches require. These processes of silyloxyarenes provide reactivity complementary to widely used phenol derivatives such as aryl pivalates, carbamates, and methyl ethers, thus enabling a powerful strategy for sequential chemoselective derivatization of complex substrates without protecting group and activating group manipulations.
