- Ligand-Free Iron-Catalyzed Regioselectivity-Controlled Hydroboration of Aliphatic Terminal Alkenes
-
The control of regioselectivities has been recognized as the elementary issue for alkene hydroboration. Despite considerable progress, the specificity of alkene substrates or the adjustment of ligands was necessary for specific regioselectivities, which r
- Cheng, Qiushi,Fan, Shi-Ming,Han, Jian-Rong,Jiang, Yuan-Ye,Liu, Shouxin,Qiao, Rui-Xiao,Su, Wei,Tian, Xia,Zhen, Xiao-Li
-
-
Read Online
- Practical and Modular Construction of C(sp3)-Rich Alkyl Boron Compounds
-
Alkyl boronic acids and esters play an important role in the synthesis of C(sp3)-rich medicines, agrochemicals, and material chemistry. This work describes a new type of transition-metal-free mediated transformation to enable the construction of C(sp3)-rich and sterically hindered alkyl boron reagents in a practical and modular manner. The broad generality and functional group tolerance of this method is extensively examined through a variety of substrates, including synthesis and late-stage functionalization of scaffolds relevant to medicinal chemistry. The strategic significance of this approach, with alkyl boronic acids as linchpins, is demonstrated through various downstream functionalizations of the alkyl boron compounds. This two-step concurrent cross-coupling approach, resembling formal and flexible alkyl-alkyl couplings, provides a general entry to synthetically challenging high Fsp3-containing drug-like scaffolds.
- Yang, Yangyang,Tsien, Jet,Ben David, Ayala,Hughes, Jonathan M. E.,Merchant, Rohan R.,Qin, Tian
-
p. 471 - 480
(2021/01/13)
-
- Metal catalyst-free photo-induced alkyl C-O bond borylation
-
Metal catalyst free, blue visible light-induced C-O bond borylation of unactivated tertiary alkyl methyl oxalates has been developed to furnish tertiary alkyl boronates. From the secondary alcohols activated with imidazolylthionyl, moderate yields of boronates were attained under standard photo-induced conditions. Preliminary mechanistic studies confirmed the involvement of a (DMF)2-B2cat2 adduct that weakly absorbs light at 437 nm so as to initiate a Bcat radical. A radical-chain process is proposed wherein the alkyl radical is engaged. This journal is
- Chen, Changzhou,Gong, Hegui,Lei, Chuanhu,Ma, Guobin,Talukdar, Sangita,Zhao, Xinluo
-
supporting information
p. 10219 - 10222
(2020/09/18)
-
- Method for synthesizing secondary or tertiary alkyl borate through iron catalytic Markovnikov selective hydroboration of olefins
-
The invention relates to a method for synthesizing secondary or tertiary alkyl borate through iron catalytic Markovnikov selective hydroboration of olefins, wherein the secondary or tertiary alkyl borate is generated by using an alkyl-substituted terminal
- -
-
Paragraph 0034-0037
(2019/12/25)
-
- Iron catalytic system for synthesizing alkyl borate through aliphatic olefin hydroboration reaction and application method thereof
-
The invention relates to an iron catalytic system for synthesizing alkyl borate through aliphatic olefin hydroboration reaction and an application method of the iron catalytic system, ferric salt is used as a catalyst, diboron ester is used as a boron sou
- -
-
Paragraph 0046-0049
(2019/12/02)
-
- Manganese-Catalyzed Borylation of Unactivated Alkyl Chlorides
-
The use of low-cost manganese(II) bromide (MnBr2) and tetramethylethylenediamine (TMEDA) catalyzes the cross coupling of (bis)pinacolatodiboron with a wide range of alkyl halides, demonstrating the first manganese-catalyzed coupling with alkyl electrophiles. This method allows access to primary, secondary, and tertiary boronic esters from the parent chlorides, which were previously inaccessible as coupling partners. The reaction proceeds in high yield with as little as 1000 ppm catalyst loading, while 5 mol % can provide high yields in as little as 30 min. Finally, radical-clock experiments revealed that at 0 °C direct borylation outcompetes alternative radical processes, thereby providing synthetically useful, temperature-controlled reaction outcomes.
- Atack, Thomas C.,Cook, Silas P.
-
p. 6139 - 6142
(2016/06/09)
-
- Iron-catalyzed borylation of alkyl electrophiles
-
The use of low-cost iron(III) acetoacetate (Fe(acac)3) and tetramethylethylenediamine (TMEDA) enables the direct cross-coupling of alkyl halides with bis(pinacolato)diboron. This approach allows for the borylation of activated or unactivated primary, secondary, and tertiary bromides. Moreover, even the borylation of benzylic or allylic chlorides, tosylates, and mesylates are possible. The reactions proceed under mild conditions at room temperature and show broad functional-group compatibility and "robustness" as measured by a modified Glorius robustness screen.
- Atack, Thomas C.,Lecker, Rachel M.,Cook, Silas P.
-
p. 9521 - 9523
(2014/07/22)
-