287172-66-1Relevant articles and documents
Formation of quaternary carbons through cobalt-catalyzed C(sp3)-C(sp3) Negishi cross-coupling
Palao, Eduardo,López, Enol,Torres-Moya, Iván,De La Hoz, Antonio,Díaz-Ortiz, ángel,Alcázar, Jesús
supporting information, p. 8210 - 8213 (2020/08/17)
Formation of all-carbon-substituted quaternary carbons is a key challenge in organic and medicinal chemistry. We report a cobalt-catalyzed C(sp3)-C(sp3) cross-coupling that allows for the introduction of benzyl, heteroarylmethylzinc and allyl groups to halo-carbonyl substrates. The cross-coupling reaction is selective for C(sp3)-over C(sp2)-halides, in contrast to most used catalytic metals, and allows access to novel scaffolds of pharmaceutical interest. NMR mechanistic studies suggest the presence of Co(0) complexes as catalytic species. This journal is
Photochemical Reductive C–C Coupling with a Guanidine Electron Donor
Wiesner, Sven,Walter, Petra,Wagner, Arne,Kaifer, Elisabeth,Himmel, Hans-J?rg
, p. 5045 - 5054 (2016/10/26)
The metal-free photoinduced reductive C–C coupling reactions of a number of substituted benzyl halides (15 examples) with the organic electron-donor 2,3,5,6-tetrakis(tetramethylguanidino)pyridine are evaluated. Depending on the substituents at the benzyl group, a C–C coupling product yield in the range 50–95 % is achieved. The photochemical benzyl-radical formation by homolytic N–C bond cleavage of the initially formed benzyl-pyridinium salts is the rate-determining step of these reactions. Electron-withdrawing as well as -donating substituents at the phenyl group increase the reaction rate. Quantum chemical computations did not reveal any correlation between either the enthalpy or Gibbs free energy of the N–C bond cleavage step and the experimentally determined first-order rate constants. Instead, the structural difference between the excited state generated by irradiation and the electronic ground state of the pyridinium ions could be used to rationalize the differences in the reaction rates.
IRON BISPHENOLATE COMPLEXES AND METHODS OF USE AND SYNTHESIS THEREOF
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Paragraph 00282; 00283; 00286, (2013/04/25)
The present application, relates to iron bisphenolate complexes and methods of use and synthesis thereof. The iron complexes are prepared from tridentate or tetradentate ligands of Formula I: wherein R1 and R2 are as defined herein. Also provided are methods and processes of using the iron bisphenolate complexes as catalysts in cross-coupling reactions and in controlled radical polymerizations.