Calcium-Catalyzed Dehydrogenative Silylation of Aromatic Ethers with Hydrosilane
作者:Lanxiao Zhao、Xianghui Shi、Jianhua Cheng
DOI:10.1021/acscatal.0c05440
日期:2021.2.19
The catalytic regioselective C–H silylation of a wide range of alkoxy-substituted benzene derivatives with primary hydrosilane was achieved by the use of scorpionate-supported calcium benzyl complex [(TpAd,iPr)Ca(p-CH2C6H4Me)(THP)] (1) (TpAd,iPr = hydrotris(3-adamantyl-5-isopropylpyrazolyl)borate, THP = tetrahydropyran) as the precatalyst. This protocol offers an atom-efficient and straightforward
广泛的烷氧基取代的苯衍生物与伯氢硅烷的催化区域选择性C–H甲硅烷基化是通过使用蝎子酸酯负载的苄基钙钙络合物[(Tp Ad,i Pr)Ca(p -CH 2 C 6 H 4 Me)(THP)](1)(Tp Ad,i Pr =氢三(3-金刚烷基-5-异丙基吡唑基)硼酸酯,THP =四氢吡喃)作前催化剂。该方案提供了一种原子高效且直接的方法,用于合成多种不具有氢受体且不含过渡金属的甲硅烷基取代的芳族醚衍生物。茴香酸钙络合物[(TP Ad,iPr)Ca(o -MeO- m- Br-C 6 H 3)](5)和[(Tp Ad,i Pr)Ca(o -Me-OCH 2 C 6 H 4)](6)建议分离出催化反应中间体并进行结构表征。
Acceleration of the Substitution of Silanes with Grignard Reagents by Using either LiCl or YCl3/MeLi
Getting up to speed: Both LiCl and the YCl3/MeLi catalyst system have an acceleration effect upon the substitution of silanesusingGrignardreagents (see scheme). The method provides access to benzyl‐, allyl‐, and arylsilanes in good yields from the starting silanes.
oxidation of organosilanes to silanols with H2O2 under neutral reaction conditions has been accomplished. A variety of organosilanes with alkyl, aryl, alknyl, and heterocyclic substituents were tolerated, as well as sterically hindered organosilanes. The oxidation appears to proceed by a concerted process involving a manganese hydroperoxide species. Featuring mild reaction conditions, fast oxidation,
在中性反应条件下,用H 2 O 2进行的第一次锰催化的有机硅烷氧化为硅烷醇。可以耐受具有烷基,芳基,炔基和杂环取代基的多种有机硅烷,以及受阻位有机硅烷。氧化似乎是通过涉及氢过氧化锰物质的协同过程进行的。该方案具有温和的反应条件,快速的氧化作用,并且没有废副产物,可实现硅烷醇和硅烷二醇的低成本,生态友好的合成。
Asymmetric Synthesis of Silicon‐Stereogenic Vinylhydrosilanes by Cobalt‐Catalyzed Regio‐ and Enantioselective Alkyne Hydrosilylation with Dihydrosilanes
作者:Huanan Wen、Xiaolong Wan、Zheng Huang
DOI:10.1002/anie.201802806
日期:2018.5.22
substitution at a stereogenic center can produce chiral silanes with significantly improved properties relative to their carbon congeners. We herein report an unprecedented cobalt‐catalyzed asymmetric hydrosilylation of unsymmetric alkynes with dihydrosilanes that furnishes silicon‐stereogenic vinylhydrosilanes with high regio‐ and enantioselectivity. The absolute configurations of the products were determined
Dehydrocoupling of alkoxyarenes with aromatic hydrosilanes catalyzed by scandium aminobenzyl complexes
作者:A. I. Babkin、A. A. Kissel、A. M. Ob’edkov、A. A. Trifonov
DOI:10.1007/s11172-022-3614-z
日期:2022.9
Scandium tris(o-aminobenzyl) complex Sc(o-CH2C6H4NMe2)3 (1) and its cationic derivative [Sc(o-CH2C6H4NMe2)2][B(C6F5)4] (2) catalyze the dehydrocoupling of alkoxyarenes with various aromatic hydrosilanes in toluene at 90 °C to give C-H silylation products in 15–89% yields (24 h). The product yield depends on the nature and the ratio of the substrates, and the new carbon-silicon bond is formed only in
三( o-氨基苄基)钪配合物Sc( o - CH 2 C 6 H 4 NMe 2 ) 3 ( 1 )及其阳离子衍生物[Sc( o - CH 2 C 6 H 4 NMe 2 ) 2 ][B(C 6 F 5 ) 4 ] ( 2) 在 90 °C 的甲苯中催化烷氧基芳烃与各种芳族氢硅烷的脱氢偶联,以 15-89% 的收率 (24 小时) 得到 CH 甲硅烷基化产物。产物收率取决于底物的性质和比例,新的碳-硅键仅在芳环中烷氧基取代基的邻位形成。阳离子络合物2被证明是一种比中性络合物1更具活性的脱氢偶联催化剂,并提供 55-89%对15-45% 的底物转化率。根据 NMR 光谱数据,配合物1在催化反应中与两种底物发生反应。1与苯甲醚的反应伴随邻位后者的金属化反应得到配合物 ( o -CH 2 C 6 H 4 NMe 2 ) 2 Sc( o -C 6 H 4 OMe) ( 4 ),而与 PhSiH 3反应得到氢化物