Iridium-Catalyzed Borylation of Secondary Benzylic C–H Bonds Directed by a Hydrosilane
摘要:
Most functionalizations of C-H bonds by main-group reagents occur at aryl or methyl groups. We describe a highly regioselective borylation of secondary benzylic C-H bonds catalyzed by an iridium precursor and 3,4,7,8-tetramethyl-1,10-phenanthroline as the ligand. The reaction is directed to the benzylic position by a hydrosilyl substituent. This hydrosilyl directing group is readily deprotected or transformed to other functional groups after the borylation reaction, providing access to a diverse set of secondary benzylboronate esters by C-H borylation chemistry.
novel route to afford 1,1-diarylalkane derivatives from simple and readily available alkyl and aryl halides in good yields and excellent regioselectivities under mild conditions. The procedure shows good tolerance for a broad variety of functional groups and both primary and secondary alkyl halides can be used. Furthermore, the reaction was successfully scaled up to the multigram scale proving the
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S: An Alternative Hydride Source for NiH‐Catalyzed Reductive Migratory Hydroarylation and Hydroalkenylation of Alkenes
作者:Jiandong Liu、Hegui Gong、Shaolin Zhu
DOI:10.1002/ejoc.202100005
日期:2021.3.12
The inexpensive borane dimethylsulfide (BMS) complex was found to be an efficient hydride source for nickel‐hydride catalyzed migratory hydrofunctionalization. Using BMS, migratory hydroarylation and migratory hydroalkenylation were achieved with broad substrate scope under mild conditions.
Ligand‐Enabled Nickel‐Catalyzed Redox‐Relay Migratory Hydroarylation of Alkenes with Arylborons
作者:Yuli He、Chuang Liu、Lei Yu、Shaolin Zhu
DOI:10.1002/anie.202001742
日期:2020.6.2
A redox-relay migratory hydroarylation of isomeric mixtures of olefins with arylboronic acids catalyzed by nickel complexes bearing diamine ligands is described. A range of structurally diverse 1,1-diarylalkanes, including those containing a 1,1-diarylated quaternary carbon, were obtained in excellent yields and with high regioselectivity. Preliminary experimental evidence supports the proposed non-dissociated
Nickel‐Catalyzed Electrochemical Reductive Relay Cross‐Coupling of Alkyl Halides to Aryl Halides
作者:Ke‐Jin Jiao、Dong Liu、Hong‐Xing Ma、Hui Qiu、Ping Fang、Tian‐Sheng Mei
DOI:10.1002/anie.201912753
日期:2020.4.16
A highly regioselective Ni-catalyzed electrochemical reductive relay cross-coupling between an aryl halide and an alkylhalide has been developed in an undivided cell. Various functional groups are tolerated under these mild reaction conditions, which provides an alternative approach for the synthesis of 1,1-diarylalkanes.
ligand-controlled nickel migration/arylation. This general protocol allows the use of abundant and bench-stable alkyl bromides and aryl bromides for the synthesis of a wide range of structurally diverse 1,1-diarylalkanes in excellent yields and high regioselectivities under mild conditions. We also demonstrated that alkyl bromide could be replaced by the proposed olefin intermediate while using n-propyl bromide/Mn0