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
Organozinc-mediated direct cross-coupling under microwave irradiation
作者:Chun-Jing Li
DOI:10.1177/17475198211026479
日期:2021.9
direct cross-coupling reaction between (het)aryl pivalates/tosylates and di(het)arylzinc species in 2-methyltetrahydrofuran/N-methyl pyrrolidone (1:1), which occurs via C–O bond cleavage undermicrowaveirradiation. The reaction takes place smoothly in short reaction times without the addition of any catalyst or ligand. The reaction is suitable for a broad scope of substrates and exhibits good functional
Cobalt-Catalyzed Biaryl Couplings via C–F Bond Activation in the Absence of Phosphine or NHC Ligands
作者:Juan Wei、Kun-Ming Liu、Xin-Fang Duan
DOI:10.1021/acs.joc.6b02354
日期:2017.2.3
Co-catalyzed biaryl coupling through C–F cleavage under phosphine or NHC-free conditions was described. A broad range of aryl fluorides including unactivated fluorides as well as those with sensitive functionalities could couple with various Ti(OEt)4-mediated aryl Grignard reagents with high selectivity under the catalysis of CoCl2/DMPU. Importantly, selective C–F bond activationcouplings between two types
Substitution of the Nitro Group with Grignard Reagents: Facile Arylation and Alkenylation of Pyridine <i>N</i>-Oxides
作者:Fang Zhang、Song Zhang、Xin-Fang Duan
DOI:10.1021/ol3026632
日期:2012.11.2
unprecedented substitution of a nitro group with aryl or alkenyl groups of Grignard reagents affords 2-aryl or alkenylpyridine N-oxides in modest to high yields with high chemoselectivity. This protocol allows a simple and clean synthesis of various 2-substituted pyridineN-oxides and the corresponding pyridine derivatives. Furthermore, straightforward one-pot iterative functionality of pyridineN-oxides could
Is Fe-catalyzed <i>ortho</i> C–H Arylation of Benzamides Sensitive to Steric Hindrance and Directing Group?
作者:Yi-Ming Wei、Meng-Fei Wang、Xin-Fang Duan
DOI:10.1021/acs.orglett.9b02359
日期:2019.8.16
The previously reported Fe-catalyzed ortho C–H arylation of benzamides relied on bi- or tridentate amide groups and specific iron ligands and was sensitive to steric hindrance. By using new mixed titanates, our present protocol accommodates various weakly coordinating benzamides and tolerates high steric hindrance and sensitive functional groups only under the catalysis of FeCl3 and TMEDA. A wide range