- Bottom-Up Meets Top-Down: Patchy Hybrid Nonwovens as an Efficient Catalysis Platform
-
Heterogeneous catalysis with supported nanoparticles (NPs) is a highly active field of research. However, the efficient stabilization of NPs without deteriorating their catalytic activity is challenging. By combining top-down (coaxial electrospinning) and bottom-up (crystallization-driven self-assembly) approaches, we prepared patchy nonwovens with functional, nanometer-sized patches on the surface. These patches can selectively bind and efficiently stabilize gold nanoparticles (AuNPs). The use of these AuNP-loaded patchy nonwovens in the alcoholysis of dimethylphenylsilane led to full conversion under comparably mild conditions and in short reaction times. The absence of gold leaching or a slowing down of the reaction even after ten subsequent cycles manifests the excellent reusability of this catalyst system. The flexibility of the presented approach allows for easy transfer to other nonwoven supports and catalytically active NPs, which promises broad applicability.
- Sch?bel, Judith,Burgard, Matthias,Hils, Christian,Dersch, Roland,Dulle, Martin,Volk, Kirsten,Karg, Matthias,Greiner, Andreas,Schmalz, Holger
-
-
Read Online
- Tea-bag-like polymer nanoreactors filled with gold nanoparticles
-
Gold-containing polymer nanotubes, which showed both catalytic activity and resistance to leaching, were prepared by the "tubes by fiber templates" (TUFT) process. For this purpose, electrospun polymer nonwovens with incorporated poly(L-lactide)-stabilize
- Mitschang, Fabian,Schmalz, Holger,Agarwal, Seema,Greiner, Andreas
-
-
Read Online
- Manganese-Catalyzed Dehydrogenative Silylation of Alkenes following Two Parallel Inner-Sphere Pathways
-
We report on an additive-free Mn(I)-catalyzed dehydrogenative silylation of terminal alkenes. The most active precatalyst is the bench-stable alkyl bisphosphine Mn(I) complex fac-[Mn(dippe)(CO)3(CH2CH2CH3)]. The catalytic process is initiated by migratory insertion of a CO ligand into the Mn-alkyl bond to yield an acyl intermediate which undergoes rapid Si-H bond cleavage of the silane HSiR3 forming the active 16e- Mn(I) silyl catalyst [Mn(dippe)(CO)2(SiR3)] together with liberated butanal. A broad variety of aromatic and aliphatic alkenes was efficiently and selectively converted into E-vinylsilanes and allylsilanes, respectively, at room temperature. Mechanistic insights are provided based on experimental data and DFT calculations revealing that two parallel reaction pathways are operative: an acceptorless reaction pathway involving dihydrogen release and a pathway requiring an alkene as sacrificial hydrogen acceptor.
- Weber, Stefan,Glavic, Manuel,St?ger, Berthold,Pittenauer, Ernst,Podewitz, Maren,Veiros, Luis F.,Kirchner, Karl
-
supporting information
p. 17825 - 17832
(2021/11/04)
-
- Charge Modified Porous Organic Polymer Stabilized Ultrasmall Platinum Nanoparticles for the Catalytic Dehydrogenative Coupling of Silanes with Alcohols
-
Developing an ideal stabilizer to prevent the aggregation of nanoparticles is still a big challenge for the practical application of noble metal nanocatalysts. Herein, we develop a charge (NTf2?) modified porous organic polymer (POP-NTf2) to stabilize ultrasmall platinum nanoparticles. The catalyst is characterized and applied in the catalytic dehydrogenative coupling of silanes with alcohols. The catalyst exhibits excellent catalytic performance with highly dispersed ultrasmall platinum nanoparticles (ca. 2.22?nm). Moreover, the catalyst can be reused at least five times without any performance significant loss and Pt NPs aggregation. Graphic Abstract: [Figure not available: see fulltext.]
- Chen, Chao,Cheng, Dan,Ding, Shunmin,Liang, Sanqi,Liu, Senqun,Ma, Xiaohua,Su, Tongtong,Wu, Shaohua,Zeng, Rong
-
-
- Photocatalyzed cross-dehydrogenative coupling of silanes with alcohols and water
-
An efficient method for the dehydrogenative coupling of silanes with alcohols under photocatalysis was developed. The reaction proceeded in the presence of Ru(bpy)3Cl2(0.5 mol%) under visible light irradiation in acetonitrile at room temperature. The developed methodology was also applicable for the synthesis of silanols using water as a coupling partner.
- Lv, Haiping,Laishram, Ronibala Devi,Chen, Jingchao,Khan, Ruhima,Zhu, Yuanbin,Wu, Shiyuan,Zhang, Jianqiang,Liu, Xingyuan,Fan, Baomin
-
supporting information
p. 3660 - 3663
(2021/04/16)
-
- Half-sandwich ruthenium(ii) complexes with tethered arene-phosphinite ligands: Synthesis, structure and application in catalytic cross dehydrogenative coupling reactions of silanes and alcohols
-
The preparation of the tethered arene-ruthenium(ii) complexes [RuCl2{η6:κ1(P)-C6H5(CH2)nOPR2}] (R = Ph, n = 1 (9a), 2 (9b), 3 (9c); R = iPr, n = 1 (10a), 2 (10b), 3 (10c)) from the corresponding phosphinite ligands R2PO(CH2)nPh (R = Ph, n = 1 (1a), 2 (1b), 3 (1c); R = iPr, n = 1 (2a), 2 (2b), 3 (2c)) is presented. Thus, in a first step, the treatment at room temperature of tetrahydrofuran solutions of dimers [{RuCl(μ-Cl)(η6-arene)}2] (arene = p-cymene (3), benzene (4)) with 1-2a-c led to the clean formation of the corresponding mononuclear derivatives [RuCl2(η6-p-cymene){R2PO(CH2)nPh}] (5-6a-c) and [RuCl2(η6-benzene){R2PO(CH2)nPh}] (7-8a-c), which were isolated in 66-99% yield. The subsequent heating of 1,2-dichloroethane solutions of these compounds at 120 °C allowed the exchange of the coordinated arene. The substitution process proceeded faster with the benzene derivatives 7-8a-c, from which complexes 9-10a-c were generated in 61-82% yield after 0.5-10 h of heating. The molecular structures of [RuCl2(η6-p-cymene){iPr2PO(CH2)3Ph}] (6c) and [RuCl2{η6:κ1(P)-C6H5(CH2)nOPiPr2}] (n = 1 (10a), 2 (10b), 3 (10c)) were unequivocally confirmed by X-ray diffraction methods. In addition, complexes [RuCl2{η6:κ1(P)-C6H5(CH2)nOPR2}] (9-10a-c) proved to be active catalysts for the dehydrogenative coupling of hydrosilanes and alcohols under mild conditions (r.t.). The best results were obtained with [RuCl2{η6:κ1(P)-C6H5(CH2)3OPiPr2}] (10c), which reached TOF and TON values up to 117 600 h-1 and 57 000, respectively.
- González-Fernández, Rebeca,Crochet, Pascale,Cadierno, Victorio
-
p. 210 - 222
(2019/12/28)
-
- Coexistence of Cu(ii) and Cu(i) in Cu ion-doped zeolitic imidazolate frameworks (ZIF-8) for the dehydrogenative coupling of silanes with alcohols
-
Recently, metal-ion-doped zeolitic imidazolate frameworks have gained considerable attention for their structure tailorability and potential catalytic applications. Herein, Cu ion-doped ZIF-8 nanocrystals were successfully prepared by the mechanical grind
- Dai, Yan,Xing, Peng,Cui, Xiaoqin,Li, Zhihong,Zhang, Xianming
-
p. 16562 - 16568
(2019/11/19)
-
- High Production of Hydrogen on Demand from Silanes Catalyzed by Iridium Complexes as a Versatile Hydrogen Storage System
-
The catalytic dehydrogenative coupling of silanes and alcohols represents a convenient process to produce hydrogen on demand. The catalyst, an iridium complex of the formula [IrCp?(Cl)2(NHC)] containing an N-heterocyclic carbene (NHC) ligand functionalized with a pyrene tag, catalyzes efficiently the reaction at room temperature producing H2 quantitatively within a few minutes. As a result, the dehydrogenative coupling of 1,4-disilabutane and methanol enables an effective hydrogen storage capacity of 4.3 wt % that is as high as the hydrogen contained in the dehydrogenation of formic acid, positioning the silane/alcohol pair as a potential liquid organic hydrogen carrier for energy storage. In addition, the heterogenization of the iridium complex on graphene presents a recyclable catalyst that retains its activity for at least 10 additional runs. The homogeneous distribution of catalytic active sites on the basal plane of graphene prevents diffusion problems, and the reaction kinetics are maintained after immobilization.
- Ventura-Espinosa, David,Sabater, Sara,Carretero-Cerdán, Alba,Baya, Miguel,Mata, Jose A.
-
p. 2558 - 2566
(2018/03/13)
-
- Platinum Complexes with a Phosphino-Oxime/Oximate Ligand
-
The platinum(II) complex [PtCl2(COD)] (2; COD = 1,5-cyclooctadiene) reacted with 1 and 2 equiv. of 2-(diphenylphosphanyl)benzaldehyde oxime (1) to generate [PtCl2{κ2-(P,N)-2-Ph2PC6H4CH=NOH}] (3) and [Pt{κ2-(P,N)-2-Ph2PC6H4CH=NOH}2][Cl]2 (4), respectively. Deprotonation of the oxime hydroxyl group of 3 with Na2CO3 led to the selective formation of the dinuclear species (μ-O)-[PtCl{κ2-(P,N)-2-Ph2PC6H4CH=NO}]2 (5), while the related methylated derivative (μ-O)-[PtMe{κ2-(P,N)-2-Ph2PC6H4CH=NO}]2 (7) could be obtained from the direct reaction of [PtMe2(COD)] (6) with the phosphino-oxime ligand 1. In the case of 4, its treatment with Na2CO3 yielded complex [Pt({κ2-(P,N)-2-Ph2PC6H4CH=NO}2H)][Cl] (8), as a result of the deprotonation of only one of the OH groups of 4. On the other hand, contrary to what was observed with 6, no deprotonation of the oxime occurred in the reaction of [PtMe3I]4 (9) with 1, from which the mononuclear PtIV derivative fac-[PtIMe3{κ2-(P,N)-2-Ph2PC6H4CH=NOH}] (10) was isolated. The solid-state structures of compounds 3, 4, 7 and 10 were determined by X-ray crystallography. In addition, the potential of all the synthesized complexes as catalysts for the dehydrogenative coupling of hydrosilanes with alcohols is also briefly discussed.
- Francos, Javier,Borge, Javier,Conejero, Salvador,Cadierno, Victorio
-
p. 3176 - 3186
(2018/07/31)
-
- Cationic rhenium(iii) complexes: synthesis, characterization, and reactivity for hydrosilylation of aldehydes
-
A series of novel cationic Re(iii) complexes [(DAAm)Re(CO)(NCCH3)2][X] [DAAm = N,N-bis(2-arylaminoethyl)methylamine; aryl = C6F5 (a), Mes (b)] [X = OTf (2), BArF4 [BArF4 = tetrakis[3,5-(trifluoromethyl)phenyl]borate] (3), BF4 (4), PF6 (5)], and their analogue [(DAmA)Re(CO)(Cl)2] [DAmA = N,N-bis(2-arylamineethyl)methylamino; aryl = C6F5] (6) were synthesized. The catalytic efficiency for the hydrosilylation reaction of aldehydes using 4a (0.03 mol%) has been demonstrated to be significantly more active than rhenium catalysts previously reported in the literature. The data suggest that electron-withdrawing substituents at the diamido amine ligand increase the catalytic efficiency of the complexes. Excellent yields were achieved at ambient temperature under neat conditions using dimethylphenylsilane. The reaction affords TONs of up to 9200 and a TOF of up to 126 h-1. Kinetic and mechanistic studies were performed, and the data suggest that the reaction is via a non-hydride ionic hydrosilylation mechanism.
- Pérez, Damaris E.,Smeltz, Jessica L.,Sommer, Roger D.,Boyle, Paul D.,Ison, Elon A.
-
p. 4609 - 4616
(2017/04/11)
-
- Synthesis of nitrogen and sulfur co-doped hierarchical porous carbons and metal-free oxidative coupling of silanes with alcohols
-
Hierarchically porous N and S co-doped carbon was prepared by using 2,5-dihydroxy-1,4-benzoquinone as the carbon source, thiourea as the N and S source, and SiO2 particles as the template. Using the material as the catalyst, oxidative coupling of silanes with alcohols was conducted for the first time under metal-free conditions.
- Chen, Bingfeng,Li, Fengbo,Mei, Qingqing,Yang, Youdi,Liu, Huizhen,Yuan, Guoqing,Han, Buxing
-
supporting information
p. 13019 - 13022
(2017/12/15)
-
- Catalytic Dehydrogenative Coupling of Hydrosilanes with Alcohols for the Production of Hydrogen On-demand: Application of a Silane/Alcohol Pair as a Liquid Organic Hydrogen Carrier
-
The compound [Ru(p-cym)(Cl)2(NHC)] is an effective catalyst for the room-temperature coupling of silanes and alcohols with the concomitant formation of molecular hydrogen. High catalyst activity is observed for a variety of substrates affording quantitative yields in minutes at room temperature and with a catalyst loading as low as 0.1 mol %. The coupling reaction is thermodynamically and, in the presence of a Ru complex, kinetically favourable and allows rapid molecular hydrogen generation on-demand at room temperature, under air, and without any additive. The pair silane/alcohol is a potential liquid organic hydrogen carrier (LOHC) for energy storage over long periods in a safe and secure way. Silanes and alcohols are non-toxic compounds and do not require special handling precautions such as high pressure or an inert atmosphere. These properties enhance the practical applications of the pair silane/alcohol as a good LOHC in the automotive industry. The variety and availability of silanes and alcohols permits a pair combination that fulfils the requirements for developing an efficient LOHC.
- Ventura-Espinosa, David,Carretero-Cerdán, Alba,Baya, Miguel,García, Hermenegildo,Mata, Jose A.
-
supporting information
p. 10815 - 10821
(2017/08/18)
-
- Metal-Free Ammonium Iodide Catalyzed Oxidative Dehydrocoupling of Silanes with Alcohols
-
An ammonium iodide catalyzed direct oxidative coupling of silanes with alcohols to give various alkoxysilane derivatives was discovered. tert -Butyl hydroperoxide proved to be an efficient oxidant for this transformation. Attractive features of this protocol include its transition-metal-free nature and the mild reaction conditions.
- Yuan, Yan-Qin,Kumar, Pailla Santhosh,Guo, Sheng-Rong
-
supporting information
p. 1620 - 1623
(2017/08/11)
-
- Dehydrogenative coupling of silanes with alcohols catalyzed by Cu3(BTC)2
-
Cu3(BTC)2 is an efficient and reusable heterogeneous catalyst for the dehydrogenative coupling of silanes with alcohols. Activity data and CO adsorption suggest that Cu(ii) and in situ generated Cu(i) are the active species. Other MOFs such as Fe(BTC), MIL-101(Cr) and UiO-66(Zr) are unable to promote this cross-coupling.
- Dhakshinamoorthy, Amarajothi,Concepcion, Patricia,Garcia, Hermenegildo
-
supporting information
p. 2725 - 2728
(2016/02/19)
-
- Silica-supported ultra small gold nanoparticles as nanoreactors for the etherification of silanes
-
Ultra small gold nanoparticles supported by porous silica (Au-SiO2) were successfully synthesized. Due to enrichment of reactants by silica, the Au-SiO2 particles functioned as nanoreactors for catalytic etherification of silanes wit
- Wang, Cui,Lin, Xijie,Ge, Yuzhen,Shah, Zameer Hussain,Lu, Rongwen,Zhang, Shufen
-
p. 102102 - 102108
(2016/11/09)
-
- Copper nanoparticles supported on doped graphenes as catalyst for the dehydrogenative coupling of silanes and alcohols
-
Copper nanoparticles (NPs) supported on a series of undoped and doped graphene materials (Gs) have been obtained by pyrolysis of alginate or chitosan biopolymers, modified or not with boric acid, containing Cu2+ ions at 900 °C under inert atmosphere. The resulting Cu-G materials containing about 17 wt% Cu NPs (from 10 to 200 nm) exhibit high catalytic activity for the dehydrogenative coupling of silanes with alcohols. The optimal material consisting on Cu-(B)G is more efficient than Cu NPs on other carbon supports.
- Blez, Juan F.,Primo, Ana,Asiri, Abdullah M.,lvaro, Mercedes,Garc, Hermenegildo
-
supporting information
p. 12581 - 12586
(2015/04/16)
-
- Homobimetallic rhodium NHC complexes as versatile catalysts for hydrosilylation of a multitude of substrates in the presence of ambient air
-
Two recently reported air- and water-stable di-Rh complexes based on 1,3-bis(3′-butylbenzimidazol-2′-ylidene)benzene were utilized as catalysts for hydrosilylation. Among the substrates investigated were aldehydes, ketones, α,β-unsaturated carbonyls, acyl chlorides, nitriles, alkenes, nitro groups, isocyanates, and tertiary amides. Additionally, carbon dioxide underwent hydrosilylation to produce dimethylphenylsilylformate. The catalysts compared well to other previously reported hydrosilylation catalysts, and the Rh-Cl catalyst was found to be faster and more selective than the Rh-I complex in each case.
- Huckaba, Aron J.,Hollis, T. Keith,Reilly, Sean W.
-
p. 6248 - 6256
(2013/12/04)
-
- Highly efficient etherification of silanes by using a gold nanoparticle catalyst: Remarkable effect of O2
-
O2 is acting! A nanosized hydroxylapatite-supported Au nanoparticle (NP) catalyst exhibited high activity under aerobic conditions, and various silyl ethers could be obtained from diverse combinations of silanes with alcohols. Moreover, O2 was found to act not as a stoichiometric oxidizing reagent, but as a non-consumed promoter, significantly boosting the catalytic activity of AuNPs (see figure). Copyright
- Mitsudome, Takato,Yamamoto, Yuya,Noujima, Akifumi,Mizugaki, Tomoo,Jitsukawa, Koichiro,Kaneda, Kiyotomi
-
supporting information
p. 14398 - 14402
(2013/11/06)
-
- Enhanced catalytic activity of self-assembled-monolayer-capped gold nanoparticles
-
An unprecedented substrate-selective catalytic enhancement effect of an alkanethiol-self-assembled monolayer (SAM) on Au nanoparticles (AuNPs) is reported. In the supported 2D-array of AuNPs, the alkanethiol-SAM acts as a protein-like soft reaction space
- Taguchi, Tomoya,Isozaki, Katsuhiro,Miki, Kazushi
-
p. 6462 - 6467
(2013/02/23)
-
- An efficient solvent-free route to silyl esters and silyl ethers
-
Dinuclear metal complexes, especially (p-cymene)ruthenium dichloride dimer {[RuCl2(p-cymene)]2}, have been found to exhibit high catalytic performance for the dehydrosilylation of various kinds of carboxylic acids and alcohols. The dehydrosilylation with [RuCl2(p-cymene)] 2 proceeded efficiently with only one equivalent of silane with respect to substrate (carboxylic acids or alcohols) under solvent-free conditions to give the corresponding silyl esters and ethers in excellent yields with a high turnover number (TON) and frequency (TOF). The 1H NMR spectrum of a toluene-d8 solution of [RuCl2(p-cymene)] 2 and a silane showed a signal assignable to the ruthenium hydride species. In contrast, no new signals were detected in the 1H NMR spectrum of a toluene-d8 solution of [RuCl2(p-cymene)] 2 and a carboxylic acid or an alcohol. There-fore, the ruthenium metal in [RuCl2(p-cymene)]2 activates a silane to afford the hydride intermediate, possibly a silylmetal hydride species. Then, the nucleophilic attack of a substrate (carboxylic acid or alcohol) to the hydride intermediate proceeds to give the corresponding silylated product. The present dehydrosilylation with an optically active silane proceeded exclusively under inversion of stereochemistry at the chiral silicon center, suggesting that the nucleophilic attack of a substrate to the hydride intermediate occurs from the backside of the ruthenium-silicon bond.
- Ojima, Yuko,Yamaguchi, Kazuya,Mizuno, Noritaka
-
scheme or table
p. 1405 - 1411
(2009/12/07)
-
- First examples of gold nanoparticles catalyzed silane alcoholysis and silylative pinacol coupling of carbonyl compounds
-
In this Letter, we illustrate the first catalytic application of supported Au nanoparticles in silane alcoholysis. The reaction proceeds with low amount of catalysts, under solvent free conditions for liquid substrates, without additional ligands and in a
- Raffa, Patrizio,Evangelisti, Claudio,Vitulli, Giovanni,Salvadori, Piero
-
p. 3221 - 3224
(2008/09/21)
-