负载在TiO 2上的可商购的Au纳米颗粒被用于催化双(频哪醇)二硼烷末端和内部炔烃的顺式硼化反应。通过使用温和的条件,更短的反应时间和比非均相Au纳米孔催化剂所需的催化剂负载低的催化剂负载量,可以以优异的产率获得产物。可以将催化系统回收并重复使用五次,而不会损失任何活性。在Au / TiO 2存在下双(频哪醇)二硼与1,2-二硅烷的组合允许σ键复分解发生并原位形成Au纳米粒子束缚的甲硅烷基硼烷。鉴于Au催化炔烃的硅烷化比相应的二甲苯化和硼氢化途径的速率快,我们能够在不直接使用甲硅烷基硼烷的情况下实现具有良好化学选择性(65-85%)的炔烃的间接硅烷化。昂贵且难以合成。
Gold-Nanoparticle-Catalyzed Mild Diboration and Indirect Silaboration of Alkynes without the Use of Silylboranes
作者:Marios Kidonakis、Manolis Stratakis
DOI:10.1002/ejoc.201700754
日期:2017.8.10
take place and the in situ formation of the Au nanoparticle-tethered silylborane. Given that the Au-catalyzed silaboration of alkynes is faster than the rates of the corresponding disilylation and diboration pathways, we were able to achieve the indirect silaboration of alkynes with good chemoselectivities (65–85 %) without the direct use of silylboranes, which are expensive and difficult to synthesize
负载在TiO 2上的可商购的Au纳米颗粒被用于催化双(频哪醇)二硼烷末端和内部炔烃的顺式硼化反应。通过使用温和的条件,更短的反应时间和比非均相Au纳米孔催化剂所需的催化剂负载低的催化剂负载量,可以以优异的产率获得产物。可以将催化系统回收并重复使用五次,而不会损失任何活性。在Au / TiO 2存在下双(频哪醇)二硼与1,2-二硅烷的组合允许σ键复分解发生并原位形成Au纳米粒子束缚的甲硅烷基硼烷。鉴于Au催化炔烃的硅烷化比相应的二甲苯化和硼氢化途径的速率快,我们能够在不直接使用甲硅烷基硼烷的情况下实现具有良好化学选择性(65-85%)的炔烃的间接硅烷化。昂贵且难以合成。
Highly efficient monophosphine platinum catalysts for alkyne diboration
作者:Rhodri Ll. Thomas、Fabio E. S. Souza、Todd B. Marder
DOI:10.1039/b010225n
日期:——
Automated parallel screening using a series of in situ generated platinum(0) phosphine complexes has allowed the identification of improved catalysts for the diboration of alkynes using bis(pinacolato)diboron (B2(pin)2, pin = OCMe2CMe2O). A selection of phosphines were added to [Pt(NBE)3] (NBE = norbornene), which contains only labile mono-olefin ligands, and the activity of the resulting solutions as catalysts for the diboration of 4-CF3C6H4CCC6H4CF3-4′
1 by B2(pin)2 was investigated by in situ GC-MS and/or NMR spectroscopy. This allowed the optimum phosphine ∶ platinum stoichiometry to be identified as 1 ∶ 1, and the large differences in catalyst activity depending on the nature of the phosphine to be quantified. The best phosphines employed in the study, PCy3 and PPh2(o-Tol) (o-Tol = C6H4Me-o), give activities orders of magnitude greater than the worst, such as P(C6F5)3 and PBut3. The monophosphine catalysts function much more efficiently than previous catalysts for a range of alkynes allowing diborations to be performed at ambient temperatures. The diboration of strained cyclic alkenes and some vinyl- and allyl-arenes proceeded well, although the catalysts were inactive for other olefinic systems examined. As a result of these studies, the isolable and stable compound [Pt(PCy3)(η2-C2H4)2] was identified as an excellent catalyst for alkyne diboration even at room temperature.
p
The stereoselective synthesis of anti isomers of γ‐boryl‐substituted homoallylic alcohols is disclosed. (E)‐1,2‐Di(boryl)alk‐1‐enes undergo Ru‐catalyzed double‐bond transposition with control of the geometry. The in situ generated (E)‐1,2‐di(boryl)alk‐2‐enes add to aldehydes in a stereospecific manner. The alkenylboron group within the product is amenable to a variety of synthetic derivatizations.
Base-catalyzed diborylation of alkynes: synthesis and applications of cis-1,2-bis(boryl)alkenes
作者:Zhijie Kuang、Guoliang Gao、Qiuling Song
DOI:10.1007/s11426-018-9344-4
日期:2019.1
An efficient, transition-metal free, and practical approach to cis-bis(boryl)alkenes from various alkynes was disclosed in the presence of a catalytic amount of K2CO3 under mild conditions. Meanwhile, tetrasubstituted alkenes and phenanthrene derivatives were readily constructed from the target diborylalkenes via Suzuki-Miyaura cross coupling.
公开了在温和条件下在催化量的K 2 CO 3存在下从各种炔烃制得的有效,无过渡金属且实用的方法来从各种炔烃中制备顺式-双(硼基)烯烃。同时,通过铃木-宫浦(Suzuki-Miyaura)交叉偶合容易地由目标二硼烷基烯烃构建四取代的烯烃和菲衍生物。
Catalytic Enantioselective Hydrogenation of Vinyl Bis(boronates)
作者:Jeremy B. Morgan、James P. Morken
DOI:10.1021/ja044396g
日期:2004.12.1
Catalytic enantioselectivehydrogenation of prochiral vinylmetallic reagents can provide an attractive alternative to hydrometalation and bismetalation of alkenes. In this contribution, the first highlyenantioselectivehydrogenation of vinyl boronic esters is described. The chiral reduction products are versatile intermediates for chemical synthesis.