Weak Coordination Promoted Regioselective Oxidative Coupling Reaction for 2,2′-Difunctional Biaryl Synthesis in Hexafluoro-2-propanol
作者:Chao Zhang、Yu Rao
DOI:10.1021/acs.orglett.5b02115
日期:2015.9.18
An unprecedented weak coordination promoted dehydrogenative cross-coupling reaction has been developed by palladium catalysis, which provides a convenient access to a wide range of 2,2′-difunctional biaryls from easily accessible substrates. Both HFIP solvent and oxidants serve as the critical factors in this new reaction. A plausible mechanism involving Pd(II)/Pd(IV) is proposed. The reaction demonstrates
Unified Protocol for Fe-Based Catalyzed Biaryl Cross-Couplings between Various Aryl Electrophiles and Aryl Grignard Reagents
作者:Lei Wang、Yi-Ming Wei、Yan Zhao、Xin-Fang Duan
DOI:10.1021/acs.joc.9b00151
日期:2019.5.3
Ti(OEt)4/PhOM enabled a highly general iron-based catalyst system, which could efficiently catalyze the biaryl coupling reaction between various electrophiles (I, Br, Cl, OTs, OCONMe2, OSO2NMe2) and common or functionalized aryl Grignardreagents with high functional group tolerance. Selective couplings of aryl iodides and bromides over the corresponding oxygen-based electrophiles have been achieved, and
Copper
<scp>porphyrin‐catalyzed</scp>
C(sp
<sup>2</sup>
)
<b>—</b>
O bond construction via coupling phenols with formamides
作者:Shuang Yang、Xiao‐Yan Chen、Ming‐Feng Xiong、Hao Zhang、Lei Shi、Dong‐Zi Lin、Hai‐Yang Liu
DOI:10.1002/jccs.202100046
日期:2021.8
construction of C(sp2)—Obond via coupling formamides with phenols was achieved firstly. A broad range of substrates afforded various carbamates in moderate to good yields with good functional group tolerance at low catalyst loading. Intermolecular competing kinetic isotope effect experiment indicated that the generation of formamide radical is the rate-determining step of current cross-dehydrogenative coupling
Room-temperature Pd-catalyzed C–H chlorination by weak coordination: one-pot synthesis of 2-chlorophenols with excellent regioselectivity
作者:Xiuyun Sun、Yonghui Sun、Chao Zhang、Yu Rao
DOI:10.1039/c3cc47431c
日期:——
A room-temperature Pd(II)-catalyzed regioselective chlorination reaction has been developed for a facile one-pot synthesis of a broad range of 2-chlorophenols. The reaction demonstrates an excellent regioselectivity and reactivity for CâH chlorination. This reaction represents one of the rare examples of mild CâH functionalization at ambient temperature.
Ruthenium-catalyzed oxidative C–H alkenylation of aryl carbamates
作者:Jie Li、Christoph Kornhaaß、Lutz Ackermann
DOI:10.1039/c2cc36196e
日期:——
A cationic ruthenium(II) catalyst enabled highly efficient oxidative alkenylations of electron-rich arenes bearing removable, weakly coordinating carbamates, and allowed for cross-dehydrogenative CâH bond functionalization in an aerobic manner.