Scope and selectivity of B(C6F5)3-catalyzed reactions of the disilane (Ph2SiH)2
作者:Peter T.K. Lee、Lisa Rosenberg
DOI:10.1016/j.jorganchem.2016.02.035
日期:2016.5
harnessing the collective, broad scope of these transformations in the preparation of new oligosilane derivatives. Borane-catalyzed hydrosilation, heterodehydrogenative coupling, and dealkylative coupling reactions of a wide range of substrates with the disilane (Ph2SiH)2 were investigated. These allowed new mono- and disubstituted disilanes to be prepared that contain SiO, SiS, and SiC linkages. Challenges
硅烷与有机底物反应中的亲电硼烷B(C 6 F 5)3的各种催化活性已在研究中得到了广泛利用,这些研究主要集中于有机合成中非常特殊,有用的官能团转化。这项研究检验了在制备新的低聚硅烷衍生物中利用这些转变的集体广泛范围的潜力。研究了硼烷催化的氢化硅烷化,杂脱氢偶联和各种基材与乙硅烷(Ph 2 SiH)2的脱烷基偶联反应。这些使得可以制备含有Si O,Si S和Si的新的单取代和二取代的乙硅烷。C链接。描述了竞争性“过度还原”化学反应所带来的挑战和机遇,并研究了催化对底物的路易斯碱度和空间位阻的敏感性。
Highly Selective Hydroxylation and Alkoxylation of Silanes: One-Pot Silane Oxidation and Reduction of Aldehydes/Ketones
作者:Nianhua Luo、Jianhua Liao、Lu Ouyang、Huiling Wen、Yuhong Zhong、Jitian Liu、Weiping Tang、Renshi Luo
DOI:10.1021/acs.organomet.9b00716
日期:2020.1.13
An efficient chemoselective iridium-catalyzed method for the hydroxylation and alkoxylation of organosilanes to generate hydrogen gas and silanols or silyl ethers was developed. A variety of sterically hindered silanes with alkyl, aryl, and ether groups were tolerated. Furthermore, this atom-economical catalytic protocol can be used for the synthesis of silanediols and silanetriols. A one-pot silane
photocatalytic hydrogen evolution cross-coupling reactions where a proton reduction cocatalyst such as a cobalt complex is generally required. Mechanistically, a silyl cation intermediate is generated to facilitate the cross-coupling reaction, which therefore represents an unprecedented approach for the generation of silyl cation via visible-light photoredox catalysis.
光氧化还原和极性反转催化的协同组合使硅烷与 H 2的析氢交叉偶联成为可能O、醇、酚和硅烷醇,它们分别以中等至极好的收率提供相应的硅烷醇、单甲硅烷基醚和二甲硅烷基醚。在仅存在有机光催化剂 4-CzIPN 和硫醇 HAT 催化剂的情况下,Si-H 和 O-H 的脱氢交叉偶联顺利进行,底物范围广,官能团相容性好,不需要任何金属、外部氧化剂和质子还原剂,这与之前报道的光催化析氢交叉偶联反应不同,后者通常需要质子还原助催化剂,如钴络合物。从机制上讲,生成甲硅烷基阳离子中间体以促进交叉偶联反应,因此代表了一种前所未有的生成甲硅烷基阳离子的方法通过可见光光氧化还原催化。