Transition metal- and light-free radical borylation of alkyl bromides and iodides using silane
作者:Beiqi Sun、Sihan Zheng、Fanyang Mo
DOI:10.1039/d1cc02134f
日期:——
for borylation of alkylbromides and iodides to alkyl boronic esters under transition metal- and light-free conditions. A series of substrates with a wide range of functional groups were effectively transformed into the borylation products in moderate to good yields. Mechanistic studies, including radical clock experiments and DFT calculations, gave detailed insight into the radical borylation process
available ketones. Mechanistic studies suggest that this Rh-catalyzed deoxygenative borylation of ketones goes through an alkene intermediate, which undergoes regiodivergent hydroboration to afford linear and branched alkylboronates. The different steric effects of PPh2Me and P(nBu)3 were found to be responsible for product selectivity by density functional theory calculations. The alkene intermediate
在这里,我们报告了一种有效的铑催化酮脱氧硼酸化合成烷基硼酸酯,其中区域选择性可以通过选择配体来切换。直链烷基硼酸酯仅在 P( n Bu) 3存在下获得,PPh 2 Me 有利于支链烷基硼酸酯的形成。该协议还允许从现成的酮中获取 1,1,2-三硼酸酯。机理研究表明,这种 Rh 催化的酮类脱氧硼酸化反应经过烯烃中间体,该中间体经历区域发散硼氢化反应,得到直链和支链烷基硼酸酯。PPh 2 Me 和 P( n Bu) 3的不同空间位阻效应通过密度泛函理论计算发现是产物选择性的原因。烯烃中间体也可以依次进行脱氢硼酸化和硼氢化反应以提供三硼酸酯。
Alkylboronic Esters from Copper-Catalyzed Borylation of Primary and Secondary Alkyl Halides and Pseudohalides
作者:Chu-Ting Yang、Zhen-Qi Zhang、Hazmi Tajuddin、Chen-Cheng Wu、Jun Liang、Jing-Hui Liu、Yao Fu、Maria Czyzewska、Patrick G. Steel、Todd B. Marder、Lei Liu
DOI:10.1002/anie.201106299
日期:2012.1.9
unprecedented copper‐catalyzed cross‐coupling reaction of the title compounds with diboron reagents is described (see scheme; Ts=4‐toluenesulfonyl). This reaction can be used to prepare both primary and secondaryalkylboronic esters having diverse structures and functional groups. The resulting products would be difficult to access by other means.
Efficient synthesis of alkylboronic esters <i>via</i> magnetically recoverable copper nanoparticle-catalyzed borylation of alkyl chlorides and bromides
作者:Mahadev L. Shegavi、Abhishek Agarwal、Shubhankar Kumar Bose
DOI:10.1039/d0gc00677g
日期:——
report a magnetically separable Cu nanocatalyst (Fe-DOPA-Cu) for the borylation of alkyl halides with alkoxy diboron reagents, providing alkylboronic esters in high yields, with broad functional group tolerance under mild reaction conditions. The procedure is also applicable to the borylation of benzyl chlorides and bromides. Radical clock experiments support a radical-mediated process. Easy recycling of
FeCl<sub>2</sub>-catalyzed hydroboration of aryl alkenes with bis(pinacolato)diboron
作者:Yang Liu、Yuhan Zhou、Huan Wang、Jingping Qu
DOI:10.1039/c5ra14869c
日期:——
Alkylboronates were synthesized by a ligand-free ferrous chloride catalyzed anti-Markovnikov hydroboration of un-activated aryl alkenes with bis(pinacolato)diboron.