IrIII metallacycle rapidly and selectively catalyses the reduction of various esters, carboxylic acids, ketones, and aldehydes. The reactions proceed in high yields at room temperature by hydrosilylation followed by desilylation. Depending on the substrate, esters are reduced to alcohols or ethers and carboxylic acids to alcohols or aldehydes.
Preparation of Nano Silica Supported Sodium Hydrogen Sulfate: As an Efficient Catalyst for the Trimethyl, Triethyl and<i>t</i>-Butyldimethyl Silylations of Aliphatic and Aromatic Alcohols in Solution and under Solvent-free Conditions
作者:Abdolreza Abri、Somayeh Ranjdar
DOI:10.1002/jccs.201300586
日期:2014.8
Nano silicasupportedsodiumhydrogensulfate has been prepared by mixing NaHSO4 with activated Nano silicagel. We wish to report a new method for the synthesis of trimethyl (TMS), triethyl (TES) and t‐butyldimethyl silyl (TBS) ethers from benzylic, allylic, propargylic alcohols, phenols, naphtholes and some of phenolic drugs in the solution and under solvent‐free conditions.
Synergistic Catalysis by Brønsted Acid/Carbodicarbene Mimicking Frustrated Lewis Pair‐Like Reactivity
作者:Yi‐Chen Chan、Yuna Bai、Wen‐Ching Chen、Hsing‐Yin Chen、Chen‐Yu Li、Ying‐Yann Wu、Mei‐Chun Tseng、Glenn P. A. Yap、Lili Zhao、Hsuan‐Ying Chen、Tiow‐Gan Ong
DOI:10.1002/anie.202107127
日期:2021.9
Carbodicarbene (CDC), unique carbenic entities bearing two lone pairs of electrons are well-known for their strong Lewis basicity. We demonstrate herein, upon introducing a weak Brønstedacid benzyl alcohol (BnOH) as a co-modulator, CDC is remolded into a Frustrated Lewis Pair (FLP)-like reactivity. DFT calculation and experimental evidence show BnOH loosely interacting with the binding pocket of CDC
Ruthenium catalyzed selective hydrosilylation of aldehydes
作者:Basujit Chatterjee、Chidambaram Gunanathan
DOI:10.1039/c3cc47593j
日期:——
A chemoselective hydrosilylation method for aldehydes is developed using a ruthenium catalyst [(Ru(p-cymene)Cl2)2] and triethylsilane; a mono hydride bridged dinuclear complex [(η6-p-cymene)RuCl}2(μ-H-μ-Cl)] and a Ru(IV) mononuclear dihydride complex [(η6-p-cymene)Ru(H)2(SiEt3)2] are identified as potential intermediates in the reaction and the proposed catalytic cycle involves a 1,3-hydride migration.
heterolytic activation of the Si–H bond. The molecular structure of a new example of such an adduct was resolved by X-ray diffraction analysis. Theoretical considerations support a donor–acceptor [C,N}Cp*IrIII-H]→[SiEt3]+ (C,N} = benzo[h]quinolinyl) formulation where the cationic silyl moiety acting as a Z ligand binds both Ir and H centers. Under the conditions of the catalysis, the latter adduct is assumed
合成了含有(五甲基环戊二烯基)铱(III)单元的一组iridacycles [C,N} Cp * Ir III -Cl](C,N} =苯并[ h ]喹啉,二苯并[ f,h ]喹啉)并衍生为与BArF型阴离子缔合的阳离子[C,N} Cp * Ir-NCMe] +。后者的盐因其在H 2中对HSiEt 3的潜在催化性能而进行了基准测试-释放测试反应。表现最佳的BArF型盐显示出能够以低的催化负载量(大约)促进反应的能力。乙腈,丙腈和一系列芳腈底物的自动串联氢化硅烷化为0.5–1 mol%。机理研究证实,Si-H键的亲电和杂合活化可初步形成硅烷-铱环加合物。通过X射线衍射分析解析了这种加合物的新实例的分子结构。理论上的考虑支持了施主-受主[C,N} Cp * Ir III -H]→[SiEt 3 ] +(C,N} =苯并[ h ]喹啉基)的配方,其中阳离子甲硅烷基部分充当Z配体结合Ir和