1228374-02-4Relevant articles and documents
Chemoselective Cross-Coupling between Two Different and Unactivated C(aryl)-O Bonds Enabled by Chromium Catalysis
Tang, Jinghua,Liu, Liu Leo,Yang, Shangru,Cong, Xuefeng,Luo, Meiming,Zeng, Xiaoming
supporting information, p. 7715 - 7720 (2020/05/20)
We report here the first example of cross-coupling between two different and unactivated C(aryl)-O bonds with chromium catalysis. The combination of a low-cost Cr(II) salt, 4,4′-di-tert-butyl-2,2′-dipyridyl (dtbpy) as the ligand, and magnesium as the reductant shows high reactivity in promoting the reductive cross-coupling of aryl methyl ether derivatives with aryl esters by cleavage and coupling of two different C(aryl)-O bonds under mild conditions. The formation of active low-valent Cr species by reduction of CrCl2 with Mg can be considered, which prefers to initially activate the C(aryl)-O bond of phenyl methyl ether with the chelation help of dtbpy and an o-imine auxiliary. The subsequent consecutive reduction, second C(aryl)-O activation, and reductive elimination allow for the achievement of selective cross-coupling of C(aryl)-O/C(aryl)-O bonds.
Oxidative Addition of Aryl Electrophiles to a Prototypical Nickel(0) Complex: Mechanism and Structure/Reactivity Relationships
Bajo, Sonia,Laidlaw, Gillian,Kennedy, Alan R.,Sproules, Stephen,Nelson, David J.
supporting information, p. 1662 - 1672 (2017/04/28)
Detailed kinetic studies of the reaction of a model Ni0 complex with a range of aryl electrophiles have been conducted. The reactions proceed via a fast ligand exchange pre-equilibrium, followed by oxidative addition to produce either [NiIX(dppf)] (and biaryl) or [NiII(Ar)X(dppf)]; the ortho substituent of the aryl halide determines selectivity between these possibilities. A reactivity scale is presented in which a range of substrates is quantitatively ranked in order of the rate at which they undergo oxidative addition. The rate of oxidative addition is loosely correlated to conversion in prototypical cross-coupling reactions. Substrates that lead to NiI products in kinetic experiments produce more homocoupling products under catalytic conditions.
Rhodium-catalyzed borylation of aryl and alkenyl pivalates through the cleavage of carbonoxygen bonds
Kinuta, Hirotaka,Hasegawa, Junya,Tobisu, Mamoru,Chatani, Naoto
supporting information, p. 366 - 368 (2015/03/30)
Rhodium-catalyzed borylation reactions of aryl and alkenyl pivalates, using a diboron reagent, via the cleavage of carbonoxygen bonds have been developed. The inert nature of the pivalate moiety enables relatively complex aryl boronates to be synthesized via the tandem cross-coupling of carbonhalogen and carbonoxygen bonds.
