- Dicarbonylative benzannulation of 3-acetoxy-1,4-enynes with CO and silylboranes by Pd and Cu cooperative catalysis: One-step access to 3-hydroxyarylacylsilanes
-
A new, general Pd/Cu-cocatalysed dicarbonylative benzannulation of 3-acetoxy-1,4-enynes with CO and silylboranes is described. The method utilizes CO as both a one-carbon (C1) unit and an external addition functional reagent to achieve an unprecedented dicarbonylative benzannulation process, and represents a facile, efficient route to 3-hydroxyarylacylsilanes. Mechanistically, the silyl-Cu intermediate formed from CuF2 and silylboranes, and silyl-Pd intermediate generated by transmetallation are two key factors for successfully targeting the reaction and selectivity.
- Wu, Li-Jun,Yang, Liang-Feng,Li, Jin-Heng,Wang, Qiu-An
-
-
Read Online
- An efficient methyltrioxorhenium(VII)-catalyzed transformation of hydrotrioxides (ROOOH) into dihydrogen trioxide (HOOOH)
-
Dihydrogen trioxide (HOOOH) is formed nearly quantitatively in the low-temperature (-70 °C) methyltrioxorhenium(VII) (MTO)-catalyzed transformation of silyl hydrotrioxides (R3SiOOOH), and some acetal hydrotrioxides, in various solvents, as confirmed by 1H, and 17O NMR spectroscopy. The calculated energetics (B3LYP) for the catalytic cycle, using H3SiOOOH as a model system, is consistent with the experimentally observed activation energy (9.5 ± 2.0 kcal/mol) and a small kinetic solvent isotope effect (kH2O/kD2O = 1.1 ± 0.1), indicating an initial concerted reaction between the silyl hydrotrioxide and MTO in the rate-determining step. With the addition of water in the next step, the intermediate undergoes a σ-bond metathesis reaction to break the Re-OOOH bond and form HOOOH, together with the second dihydroxy intermediate. The final step in the catalytic cycle involves a second, catalytic water that lowers the barrier to form H3SiOH and MTO. Copyright
- Bergant, Ana,Cerkovnik, Janez,Plesnicar, Bozo,Tuttle, Tell
-
-
Read Online
- Copper-Containing Polyoxometalate-Based Metal-Organic Framework as a Catalyst for the Oxidation of Silanes: Effective Cooperative Catalysis by Metal Sites and POM Precursor
-
The oxidation of silanes into silanols is a very necessary transformation, and yet the rational fabrication of efficient catalysts for this reaction remains a challenging task. Here, a 3D polyoxometalate-based metal-organic framework (POMOF), [Cu3(pz)3{PMo12O40}]·H2O (HENU-8, HENU = Henan University; pz = pyrazine) was consciously prepared and first employed in the oxidation of dimethylphenylsilane with tert-butyl hydroperoxide (TBHP) as an oxidant, achieving 89% yield at a production rate of 132 mmol·g-1·h-1. Control experiments indicated that polyoxometalates and Cu atoms together affected the ultimate outcome in this catalytic system, and the designed catalyst followed a free radical mechanism.
- Ma, Xinyi,Jing, Zhen,Li, Kunhong,Chen, Yian,Li, Dandan,Ma, Pengtao,Wang, Jingping,Niu, Jingyang
-
supporting information
p. 4056 - 4061
(2022/03/03)
-
- Metal-free hydrogen evolution cross-coupling enabled by synergistic photoredox and polarity reversal catalysis
-
A synergistic combination of photoredox and polarity reversal catalysis enabled a hydrogen evolution cross-coupling of silanes with H2O, alcohols, phenols, and silanols, which afforded the corresponding silanols, monosilyl ethers, and disilyl ethers, respectively, in moderate to excellent yields. The dehydrogenative cross-coupling of Si-H and O-H proceeded smoothly with broad substrate scope and good functional group compatibility in the presence of only an organophotocatalyst 4-CzIPN and a thiol HAT catalyst, without the requirement of any metals, external oxidants and proton reductants, which is distinct from the previously reported 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 cationviavisible-light photoredox catalysis.
- Cao, Jilei,Lu, Kanghui,Ma, Lishuang,Yang, Xiaona,Zhou, Rong
-
supporting information
p. 8988 - 8994
(2021/11/23)
-
- Selective Electrochemical Hydrolysis of Hydrosilanes to Silanols via Anodically Generated Silyl Cations
-
The first electrochemical hydrolysis of hydrosilanes to silanols under mild and neutral reaction conditions is reported. The practical protocol employs commercially available and cheap NHPI as a hydrogen-atom transfer (HAT) mediator and operates at room temperature with high selectivity, leading to various valuable silanols in moderate to good yields. Notably, this electrochemical method exhibits a broad substrate scope and high functional-group compatibility, and it is applicable to late-stage functionalization of complex molecules. Preliminary mechanistic studies suggest that the reaction appears to proceed through a nucleophilic substitution reaction of an electrogenerated silyl cation with H2O.
- Liang, Hao,Wang, Lu-Jun,Ji, Yun-Xing,Wang, Han,Zhang, Bo
-
supporting information
p. 1839 - 1844
(2020/12/01)
-
- Sterically encumbered tris(trialkylsilyl) phosphine precursors for quantum dot synthesis
-
The synthesis of nanomaterials with a narrow size distribution is challenging, especially for III-V semiconductor nanoparticles (also known as quantum dots). Concerning phosphides, this issue has been largely attributed the use of overly reactive precursors. The problem is exacerbated due to the narrow range of competent reagents for III-V semiconductor syntheses. We report the use of sterically encumbered tris(triethylsilyl) phosphine and tris(tributylsilyl) phosphine for InP quantum dot (QD) synthesis among others. The hypothesis was that these reagents are less reactive than the near-ubiquitous precursor tris(trimethylsilyl) phosphine and can be used to create more homogeneous materials. It was found that the InP products' quantum yields and emission color saturation (fwhm) were improved, but not to the levels realized in CdSe QDs. Regardless, these reagents have other positive attributes; they are less pyrophoric and can be applied toward the synthesis of II-V semiconductors and organophosphorus compounds. Concerning safe practices, we demonstrate that ammonium bifluoride is an effective replacement for highly toxic HF for the post-treatment of III-V semiconductor quantum dots.
- Chandrasiri, Hashini B.,Kim, Eun Byoel,Snee, Preston T.
-
p. 15928 - 15935
(2020/11/03)
-
- Highly Selective Hydroxylation and Alkoxylation of Silanes: One-Pot Silane Oxidation and Reduction of Aldehydes/Ketones
-
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 oxidation and chemoselective reduction of aldehydes/ketones was also realized.
- Luo, Nianhua,Liao, Jianhua,Ouyang, Lu,Wen, Huiling,Zhong, Yuhong,Liu, Jitian,Tang, Weiping,Luo, Renshi
-
p. 165 - 171
(2020/01/21)
-
- Selective Manganese-Catalyzed Oxidation of Hydrosilanes to Silanols under Neutral Reaction Conditions
-
The first manganese-catalyzed 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, and no waste byproducts, the protocol allows a low-cost, eco-benign synthesis of both silanols and silanediols.
- Wang, Kaikai,Zhou, Jimei,Jiang, Yuting,Zhang, Miaomiao,Wang, Chao,Xue, Dong,Tang, Weijun,Sun, Huamin,Xiao, Jianliang,Li, Chaoqun
-
supporting information
p. 6380 - 6384
(2019/05/06)
-
- Synthesis, characterization and catalytic oxidation of organosilanes with a novel multilayer polyoxomolybdate containing mixed-valence antimony
-
Oxidation of organosilanes is one of the pivotal reactions in organic synthesis and the corresponding products of silanols are widely as raw materials in industrial processes. In this paper, a new type of polyoxomolybdate containing mixed-valence antimony, [SbVSbIII4Mo18O66]7? (1a), has been isolated as tetramethyl ammonium salt in aqueous solution. The compound was structurally characterized by FT-IR, XPRD, TG, XPS, ESI–MS etc. It is the first time that the containing mixed-valence antimony polyoxomolybdate was used as a heterogeneous catalyst to efficaciously catalyze the oxidation of organosilanes to silanols under mild reaction conditions. Furthermore, the catalyst was stable and maintained its catalytic activity after three reaction cycles.
- Wang, Yaping,Lu, Jingkun,Ma, Xinyi,Niu, Yanjun,Singh, Vikram,Ma, Pengtao,Zhang, Chao,Niu, Jingyang,Wang, Jingping
-
p. 167 - 174
(2018/04/24)
-
- Method for synthesizing silanol from silane through catalytic oxidation by bipyridine manganese catalyst
-
The invention discloses a method for synthesizing silanol from silane through catalytic oxidation by a bipyridine manganese catalyst. The method employs a bipyridine manganese complex formed by coordination of a manganese salt and a dipyridine compound as a catalyst and clean environment-friendly hydrogen peroxide as an oxidizing agent for catalytic oxidation of silane into silanol. Compared with conventional methods, the method provided by the invention has the advantages that the catalyst is low in price; the preparation method is simple; raw materials are easily available; and the method is low in the usage amount of the catalyst, wide in the range of usable substrates, mild in reaction conditions, simple to operate, friendly to environment, short in reaction time, high in yield, good in selectivity, low in industrialization cost, etc.
- -
-
Paragraph 0014; 0015; 0016; 0017-0043; 0080; 0081; 0082
(2018/01/11)
-
- Wettability-Driven Palladium Catalysis for Enhanced Dehydrogenative Coupling of Organosilanes
-
Direct coupling of Si-H bonds has emerged as a promising strategy for designing chemically and biologically useful organosilicon compounds. Heterogeneous catalytic systems sufficiently active, selective, and durable for dehydrosilylation reactions under mild conditions have been lacking to date. Herein, we report that the hydrophobic characteristics of the underlying supports can be advantageously utilized to enhance the efficiency of palladium nanoparticles (Pd NPs) for the dehydrogenative coupling of organosilanes. As a result of this prominent surface wettability control, the modulated catalyst showed a significantly higher level of efficiency and durability characteristics toward the dehydrogenative condensation of organosilanes with water, alcohols, or amines in comparison to existing catalysts. In a broader context, this work illustrates a powerful approach to maximize the performance of supported metals through surface wettability modulation under catalytically relevant conditions.
- Lin, Jian-Dong,Bi, Qing-Yuan,Tao, Lei,Jiang, Tao,Liu, Yong-Mei,He, He-Yong,Cao, Yong,Wang, Yang-Dong
-
p. 1720 - 1727
(2017/08/15)
-
- Nanoporous palladium catalyzed silicon-based one-pot cross-coupling reaction of aryl iodides with organosilanes
-
One-pot cross-coupling of aryl iodides with organosilanes is realized in excellent yield by utilizing dealloyed nanoporous palladium as a sustainable and heterogeneous catalyst. The reaction is completed under mild conditions and the catalyst can be reused several times without evident loss of its catalytic activity. This journal is the Partner Organisations 2014.
- Li, Zhiwen,Lin, Sha,Ji, Lisha,Zhang, Zhonghua,Zhang, Xiaomei,Ding, Yi
-
p. 1734 - 1737
(2014/06/09)
-
- Highly selective oxidation of organosilanes with a reusable nanoporous silver catalyst
-
Room temperature highly selective oxidation of organosilanes to organosilanols and organosilyl ethers is achieved in liquid-phase with dealloyed nanoporous silver catalysts. In both cases, aromatic and aliphatic silanes can be effectively converted into the corresponding silanols and silyl ethers by using water and alcohols as oxidant, respectively. Moreover, hydrogen gas is the only by-product and the catalyst can be recycled for several times without evident loss of activity and selectivity.
- Li, Zhiwen,Zhang, Congcong,Tian, Jing,Zhang, Zhonghua,Zhang, Xiaomei,Ding, Yi
-
-
- Organocatalytic oxidation of organosilanes to silanols
-
The oxidation of organosilanes to silanols constitutes an attractive transformation for both industry and academia. Bypassing the need for stoichiometric oxidants or precious metal catalytic complexes, the first organocatalytic oxidation of silanes has been accomplished. Catalytic amounts of 2,2,2-trifluoroacetophenone, in combination with the green oxidant H 2O2, lead to excellent to quantitative yields in a short reaction time. A variety of alkyl, aryl, alkenyl, and alkynyl substituents can be tolerated, providing an easy, cheap, efficient, and practical solution to a highly desirable transformation.
- Limnios, Dimitris,Kokotos, Christoforos G.
-
p. 2239 - 2243
(2013/10/22)
-
- Surface oxygen-assisted Pd nanoparticle catalysis for selective oxidation of silanes to silanols
-
Just add O2: Based on the fact that an oxygen-adsorbed Pd metal surface shows higher reactivity for water dissociation than a clean Pd surface, carbon-supported Pd nanoparticles (NPs) with surface oxygen atoms were developed as a highly effective and reusable heterogeneous catalyst for selective oxidation of silanes to silanols with water as a green oxidant (see figure). Copyright
- Shimizu, Ken-Ichi,Kubo, Takahiro,Satsuma, Atsushi
-
supporting information; experimental part
p. 2226 - 2229
(2012/03/26)
-
- Nanostructured materials as catalysts: Nanoporous-gold-catalyzed oxidation of organosilanes with water
-
Pores to the fore: Nanoporous gold shows a remarkable catalytic activity for the oxidation of organosilane compounds with water. The catalyst is easily recoverable and can be reused several times without leaching and loss of activity. Copyright
- Asao, Naoki,Ishikawa, Yoshifumi,Hatakeyama, Naoya,Menggenbateer,Yamamoto, Yoshinori,Chen, Mingwei,Zhang, Wei,Inoue, Akihisa
-
experimental part
p. 10093 - 10095
(2011/03/16)
-
- Highly selective oxidation of organosilanes to silanols with hydrogen peroxide catalyzed by a lacunary polyoxotungstate
-
Silanol synthesis: Divacant lacunary polyoxotungstate (nBu4N+)4[g- SiW10O34(H2O)2] (I) is an efficient homogeneous catalyst for highly selective oxidation of organosilanes to silanols with 30/60% aqueous H2O2. Various kinds of silanes 1 containing aryl, alkyl, alkenyl, alkynyl and alkoxy groups are chemoselectively converted into the corresponding silanols 2 in high yields with only one equivalent of aqueous H2O2 with respect to the substrate.
- Ishimoto, Ryo,Kamata, Keigo,Mizuno, Noritaka
-
supporting information; experimental part
p. 8900 - 8904
(2010/01/16)
-
- Supported gold nanoparticle catalyst for the selective oxidation of silanes to silanols in water
-
Hydroxyapatite-supported gold nanoparticles (AuHAP) can act as highly efficient and reusable catalysts for the oxidation of diverse silanes into silanols in water; this is the first catalytic methodology for the selective synthesis of aliphatic silanols using water under organic-solvent-free conditions.
- Mitsudome, Takato,Noujima, Akifumi,Mizugaki, Tomoo,Jitsukawa, Koichiro,Kaneda, Kiyotomi
-
supporting information; experimental part
p. 5302 - 5304
(2010/01/31)
-
- Efficient heterogeneous oxidation of organosilanes to silanols catalysed by a hydroxyapatite-bound Ru complex in the presence of water and molecular oxygen
-
RuHAP is a highly selective and reusable catalyst for the oxidation of a wide variety of organosilanes to the corresponding silanols in the presence of water and molecular oxygen.
- Mori, Kohsuke,Tano, Makoto,Mizugaki, Tomoo,Ebitani, Kohki,Kaneda, Kiyotomi
-
p. 1536 - 1538
(2007/10/03)
-
- Cleavage of arylalkylsilanes by sodium amide in liquid ammonia
-
The aryl carbon-silicon bonds in arylalkyl monosilanes have been cleaved by sodium amide in liquid ammonia. Sub-stoichiometric amounts of amide effect complete cleavage of the aryl anion. Reactions were complete in just a few minutes at room temperature except when bulky alkyl groups are present (eg. triisopropylphenylsilane). In dialkyldiarylsilanes both aryl functions were rapidly cleaved with little selectivity when the aryl groups had different substituents. The influence of metallic cations was important (NaNH2, KNH2 >> LiNH2 > Ca(NH2)2). Solvent and temperature were also studied.
- Sun, Guang-Ri,He, Jin-Bao,Zhu, Hua-Jie,Pittman Jr., Charles U.
-
p. 619 - 622
(2007/10/03)
-
- GRIGNARD REAGENTS AS POWDERS : PREPARATION AND REACTIVITY
-
The TDA-1 chelating agent is able to complex Grignard reagents.This complexation leads to powders.The preparation is general and the complexes "RMgX/TDA-1" are easily prepared from every type of Grignard reagents.These solids are stable under nitrogen and can be titrated and used as Grignard reagents.The study of their chemical reactivity shows a behaviour comparable to that of conventional Grignard reagents, the rate of reactions however being decreased.Selective addition onto a mixture of aldehyde and ketone is possible.Interestingly the reactions can be performed in hydrocarbon solvents (toluene, light petroleum, cyclohexane).
- Boudin, Alain,Cerveau, Genevieve,Chuit, Claude,Corriu, Robert J.P.,Reye, Catherine
-
p. 171 - 180
(2007/10/02)
-
- OXIDATIVE CLEAVAGE OF Si-H BOND IN PRESENCE OF SILVER PERCHLORATE. PART II. KINETICS OF COMPETITIVE-CONSECUTIVE REACTION OF TRISUBSTITUTED SILANES IN BENZENE
-
Kinetics of oxygenation and dehydrogenation of trisubstituted silanes (mainly selected trialkylsilanes and trialkoxysilanes) in presence of silver perchlorate was monitored manometrically.Non-linear dependence of pseudo-first-order rate constants and the initial rates of hydrogen evolution and oxygen uptake on the silver perchlorate initial concentration shows that the reaction order in respect to AgClO4 decreases from 2 to 0 and from 1 to 0, respectively.All kinetic data and activation parameters, as well as substituent effects at silicon suggest the reaction to proceed via silane - silver perchlorate intermediates of the Arrhenius or van't Hoff type which were detected spectrophotometrically previously.
- Marciniec, Bogdan,Tran, Son
-
p. 827 - 835
(2007/10/02)
-