CO 2的化学固定受到了广泛的关注。特别是与CO 2催化形成C-C键生成羧酸具有重要意义。在CO 2固定方法中,多重羧化是具有挑战性的课题之一。在这里,我们研究了多种硼酸频哪醇酯(C(sp 2 )–、C(sp 3 )– 和 C(sp)–B 化合物)与 CO 2的 Cu 催化羧化反应,有效地提供了相应的产物,包括芳基、烯基、烷基和炔基羧酸。这种羧化也适用于在稳健的反应条件下产生二元和三元羧酸的多重CO2固定(总共29个实例)。
Tropylium-Promoted Hydroboration Reactions: Mechanistic Insights <i>Via</i> Experimental and Computational Studies
作者:Nhan N. H. Ton、Binh Khanh Mai、Thanh Vinh Nguyen
DOI:10.1021/acs.joc.1c01208
日期:2021.7.2
hydroboration reaction of alkynes. A broad range of vinylboranes can be easily accessed via this metal-free protocol. Similar hydroboration reactions of alkenes and epoxides can also be efficiently catalyzed by the same tropylium catalysts. Experimentalstudies and DFT calculations suggested that the reaction follows an uncommon mechanistic pathway, which is triggered by the hydride abstraction of pinacolborane
AgSbF<sub>6</sub>-Catalyzed <i>anti</i>-Markovnikov hydroboration of terminal alkynes
作者:Ramesh Mamidala、Vipin K. Pandey、Arnab Rit
DOI:10.1039/c8cc07499b
日期:——
AgSbF6-Catalyzed anti-Markovnikov addition of pinacolborane (HBpin) to terminal alkynes to produce the E-vinylboronates is reported. This efficient methodology is scalable, compatible with sterically and electronically diverse alkynes, and works at room temperature under solvent-free condition. The utility of this method is demonstrated in the facilesynthesis of the clinically important (E)-2,4,3′
Lithium-promoted hydroboration of alkynes and alkenes using commercially available hexamethyldisilazane lithium as a precatalyst and HBpin as a hydride source has been developed. This method will be appealing for organic synthesis because of its remarkable substrate tolerance and good yields. Mechanistic studies revealed that the hydroboration proceeds through the in situ-formed BH3 species, which
Catalyst-free and solvent-free hydroboration of alkynes
作者:Ashok Kumar Jaladi、Hyeon Seong Choi、Duk Keun An
DOI:10.1039/d0nj02612c
日期:——
The hydroboration of alkynes with pinacolborane (HBpin) under catalyst- and solvent-free conditions was demonstrated. Various alkynes were smoothly converted into alkenyl boronate esters in good to excellent yields at 110 °C. The gram-scale hydroboration of alkynes provided the corresponding boronates, which were further utilized for various chemical transformations and coupling reactions.