1220102-04-4Relevant academic research and scientific papers
General C(sp2)-C(sp3) Cross-Electrophile Coupling Reactions Enabled by Overcharge Protection of Homogeneous Electrocatalysts
Hamby, Taylor B.,Sevov, Christo S.,Truesdell, Blaise L.
supporting information, p. 5884 - 5893 (2020/04/10)
Cross-electrophile coupling (XEC) of alkyl and aryl halides promoted by electrochemistry represents an attractive alternative to conventional methods that require stoichiometric quantities of high-energy reductants. Most importantly, electroreduction can readily exceed the reducing potentials of chemical reductants to activate catalysts with improved reactivities and selectivities over conventional systems. This work details the mechanistically-driven development of an electrochemical methodology for XEC that utilizes redox-active shuttles developed by the energy-storage community to protect reactive coupling catalysts from overreduction. The resulting electrocatalytic system is practical, scalable, and broadly applicable to the reductive coupling of a wide range of aryl, heteroaryl, or vinyl bromides with primary or secondary alkyl bromides. The impact of overcharge protection as a strategy for electrosynthetic methodologies is underscored by the dramatic differences in yields from coupling reactions with added redox shuttles (generally >80%) and those without (generally 20%). In addition to excellent yields for a wide range of substrates, reactions protected from overreduction can be performed at high currents and on multigram scales.
Negishi alkyl-aryl cross-coupling catalyzed by Rh: Efficiency of novel tripodal 3-diphenylphosphino-2-(diphenylphosphino)methyl-2-methylpropyl acetate ligand
Ejiri, Syogo,Odo, Shunsuke,Takahashi, Hideki,Nishimura, Yugo,Gotoh, Kazuma,Nishihara, Yasushi,Takagi, Kentaro
supporting information; experimental part, p. 1692 - 1695 (2010/09/03)
3-Diphenylphosphino-2-(diphenylphoshino)methyl-2-methylpropyl acetate acted as an efficient ligand for a Rh catalyst, achieving cross-coupling between arylzinc compounds bearing electron-withdrawing groups and alkyl electrophiles. The beneficial effect of the tripodal ligand and such aryl nucleophiles was discussed with regard to the specificity of the Rh catalysis.
