- A ketone-functionalized Zn-MOF for solvent-free cyanosilylation of aldehyde and treatment activity against osteosarcoma trough increasing Mg63 cells autophagy
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In this work, 5,5′-carbonyldiisophthalic acid (H4cipa) was used as a ligand to react with Zn(NO3)2·6H2O in a mixed solvent of DMF and water to prepare a new metal-organic framework (MOF) with the chemical formul
- Peng, Tao,Jia, Peng,Wang, Rui,Feng, Haoyu,Han, Xiao-Ming
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Read Online
- Fully meta-Substituted 4,4′-Biphenyldicarboxylate-Based Metal–Organic Frameworks: Synthesis, Structures, and Catalytic Activities
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Fully meta-substituted 2,2′,6,6′-tetramethoxy-4,4′-biphenyldicarboxylic acid (H2L) was synthesized and applied in the construction of three metal–organic frameworks (MOFs), {[Cu3L3(H2O)2(DMF)]n (1), [Zn4OL3]n (2), and [Zn4OL3(H2O)(DEF)]n (3)}. For 1, the approximately vertical twist of two benzene rings in L leads to the formation of a twofold-interpenetrated 3D structure with 1D open channels (11 × 15 ?). MOFs 2 and 3 have classical twofold-interpenetrated isoreticular MOF structures, and reversible transformation of the oxozinc carboxylate clusters of 2 and 3 could be realized via a solvent-exchange-induced single-crystal-to-single-crystal pathway, which provides direct structural evidence for a Zn4O core as Lewis acidic site in MOFs. Desolvated framework 1′ exhibits high permanent porosity (Langmuir surface area = 555 m2/g), high thermal stability (up to 300 °C), and highly active catalytic properties for cyanosilylation and olefin epoxidation. MOF 2 exhibits moderate carbon dioxide uptake ability and can efficiently catalyze the cycloaddition of CO2 with epoxides under mild conditions.
- Li, Jiawei,Ren, Yanwei,Qi, Chaorong,Jiang, Huanfeng
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Read Online
- A Stable Porphyrin-Based Porous mog Metal-Organic Framework as an Efficient Solvent-Free Catalyst for C-C Bond Formation
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We herein report the porous 4-fold interpenetrated mog (moganite) metal-organic framework (MOF) [Cd3(tipp)(bpdc)2]·DMA·9H2O (1·Cd; H2tipp = 5,10,15,20-tetrakis(4-(imidazol-1-yl)phenyl)porphyrin, H2bpd
- Jiang, Wei,Yang, Jin,Liu, Ying-Ying,Song, Shu-Yan,Ma, Jian-Fang
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Read Online
- Imidazolinium-carbodithioate zwitterions as organocatalysts for the cyanosilylation of aldehydes
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Imidazolinium-carbodithioates as new organocatalysts have been found to catalyze the cyanosilylation of aldehydes in 100% conversion and good yields. The catalysts could be easily recovered during flash column chromatography.
- Blanrue, Amélie,Wilhelm, René
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Read Online
- Germyliumylidene: A Versatile Low Valent Group 14 Catalyst
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Bis-NHC stabilized germyliumylidenes [RGe(NHC)2]+ are typically Lewis basic (LB) in nature, owing to their lone pair and coordination of two NHCs to the vacant p-orbitals of the germanium center. However, they can also show Lewis acidity (LA) via Ge?CNHC σ* orbital. Utilizing this unique electronic feature, we report the first example of bis-NHC-stabilized germyliumylidene [MesTerGe(NHC)2]Cl (1), (MesTer=2,6-(2,4,6-Me3C6H2)2C6H3; NHC= IMe4=1,3,4,5-tetramethylimidazol-2-ylidene) catalyzed reduction of CO2 with amines and arylsilane, which proceeds via its Lewis basic nature. In contrast, the Lewis acid nature of 1 is utilized in the catalyzed hydroboration and cyanosilylation of carbonyls, thus highlighting the versatile ambiphilic nature of bis-NHC stabilized germyliumylidenes.
- Sarkar, Debotra,Dutta, Sayan,Weetman, Catherine,Schubert, Emeric,Koley, Debasis,Inoue, Shigeyoshi
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supporting information
p. 13072 - 13078
(2021/08/09)
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- n-Butyllithium as a highly efficient precatalyst for cyanosilylation of aldehydes and ketones
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A highly efficient cyanosilylation protocol mediated by the easily availablen-BuLi with a wide range of aldehydes and ketones was developed. This protocol features excellent yields with very lown-BuLi loadings (0.01-0.05 mol%) at room temperature, solvent
- Kang, Zihan,Wang, Yuhong,Xu, Xiaojuan,Xue, Mingqiang,Zhang, Wenxuan,Zhou, Shuai,Zhu, Xu
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supporting information
p. 7432 - 7437
(2021/09/07)
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- The direct trifluoromethylsilylation and cyanosilylation of aldehydes: via an electrochemically induced intramolecular pathway
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The initiator-free electrochemical trifluoromethylsilylation and cyanosilylation of aldehydes were developed in an undivided cell. A DFT study reveals that the direct cathodic activation of trimethylsilyl reagents significantly released the congestion around the 'Si' atom, allowing the Si-O bond affinity to form concerted anion intermediates with aldehydes. Thus, intramolecular -CF3 and -CN migration make the reactions much easier to carry out without initiators.
- Yang, Hui,Shen, Yongli,Xiao, Zihui,Liu, Caiyan,Yuan, Kedong,Ding, Yi
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supporting information
p. 2435 - 2438
(2020/03/06)
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- Visible-Light-Driven N-Heterocyclic Carbene Catalyzed γ- and ?-Alkylation with Alkyl Radicals
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The merging of photoredox catalysis and N-heterocyclic carbene (NHC) catalysis for γ- and ?-alkylation of enals with alkyl radicals was developed. The alkylation reaction of γ-oxidized enals with alkyl halides worked well for the synthesis γ-multisubstituted-α,β-unsaturated esters, including those with challenging vicinal all-carbon quaternary centers. The synthesis of ?-multisubstituted-α,β-γ,δ-diunsaturated esters by an unprecedented NHC-catalyzed ?-functionalization was also established.
- Dai, Lei,Xia, Zi-Hao,Gao, Yuan-Yuan,Gao, Zhong-Hua,Ye, Song
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supporting information
p. 18124 - 18130
(2019/11/13)
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- Low-valent magnesium(i)-catalyzed cyanosilylation of ketones
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The magnesium(i) complex [(XylNacnac)Mg]2 was employed as a highly efficient catalyst for the cyanosilylation of a variety of ketones with trimethylsilyl cyanide under mild conditions. In contrast to the traditional stoichiometric us
- Wang, Weifan,Luo, Man,Li, Jia,Pullarkat, Sumod A.,Ma, Mengtao
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supporting information
p. 3042 - 3044
(2018/03/28)
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- Preparation method of cyanalcohol silyl ether compound
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The invention discloses a preparation method of a cyanalcohol silyl ether compound. The preparation method comprises usage of a catalyst, the catalyst is a tridentate forceps-shaped ligand-stabilizedmagnesium lithium bimetallic compound. According to the
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Paragraph 0041; 0042; 0043
(2019/01/06)
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- Method for aldehyde cyanosilylation reaction under conditions of no catalyst or solvent
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The invention discloses a method for an aldehyde cyanosilylation reaction under conditions of no catalyst or solvent. In a glove box, aldehyde and trimethylsilyl cyanide are sequentially added to a nuclear magnetic resonance tube, then, the glove box is m
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Paragraph 0133; 0134; 0135; 0139; 0143
(2018/11/22)
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- Cationic two-dimensional inorganic networks of antimony oxide hydroxide for Lewis acid catalysis
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We have successfully synthesized a rare example of inorganic layered materials possessing a positive charge, which is well outside the isostructural set of layered double hydroxides. This layered architecture consists of two-dimensional corrugated [Sb2O2(OH)]+ layers with linear α,ω-alkanedisulfonate anions residing in the interlamellar space. This cationic material displays a chemical robustness under highly acidic aqueous conditions (pH = 1). Combining the robust nature and the high density of SbIII sites on the exposed crystal facets, our cationic layered material is an efficient, recyclable catalyst for cyanosilylation of benzaldehyde derivatives with trimethylsilyl cyanide. In addition, the Lewis acidity of the SbIII sites also catalyzes the ketalization of carbonyl groups under "green" solvent-free conditions.
- Yin, Jinlin,Fei, Honghan
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supporting information
p. 4054 - 4058
(2018/03/26)
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- Efficient and selective aldehyde cyanosilylation catalyzed by Mg-Li bimetallic complex
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A NCN-pincer ligand-based Mg-Li bimetallic complex [NCN-MgBr2][Li(THF)4] 1 has been employed as an efficient catalyst for cyanosilylation of a wide range of aldehydes with trimethylsilyl cyanide (TMSCN) at room temperature in CDClsu
- Li, Jia,Yu, Ting,Luo, Man,Xiao, Qian,Yao, Weiwei,Xu, Li,Ma, Mengtao
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- Dimeric alumatranes as catalysts for trimethylsilylcyanation reaction
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The solid-state structures of dimeric alumatranes with three five-membered rings chelated by [(OCMe2CH2)nN(CH2CH2O)3-n]3- (n = 1, L1; n = 2, L2; n = 3, L3), which vary by the num
- Kim, Yoseph,Lee, Kang Mun,Kim, So Han,Moon, Jung Hee,Kim, Youngjo
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p. 48151 - 48160
(2017/11/03)
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- Synthesis of magnetically recoverable imidazolium hydrogen carbonate and its application as an N-heterocyclic carbene catalyst to cyanosilylation of aldehydes and ketones
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We prepared a magnetically recoverable imidazolium hydrogen carbonate by immobilizing an imidazolium hydrogen carbonate on magnetite and applied it as an N-heterocyclic carbene catalyst to the cyanosilylation of aldehydes and ketones. By employing the magnetite-supported imidazolium hydrogen carbonate as a catalyst, the cyanosilylation proceeded at 60?°C to provide the corresponding trimethylsilylated cyanohydrin in a fair chemical yield. Moreover, after the reaction, the magnetic catalyst was readily recovered by use of an external magnet and could be reused up to five times.
- Fujii, Akira,Choi, Jun-Chul,Fujita, Ken-ichi
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supporting information
p. 1515 - 1518
(2017/03/24)
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- TBD-catalyzed cyanosilylation of aldehydes and ketones
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This study examines the catalytic efficacy of 1,5,7-triazabicyclo[4,4,0]dec-5-ene (TBD) in the cyanosilylation of aldehydes and ketones. In an aldehyde reaction, the corresponding products were obtained at high yield using minimal TBD (0.01 mol%). TBD was
- Matsukawa,Kimura
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p. 1947 - 1952
(2016/11/25)
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- Insight into the catalytic properties and applications of metal-organic frameworks in the cyanosilylation of aldehydes
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Here we present a systematic investigation of the cyanosilylation of aldehydes with trimethylsilyl cyanide (TMSCN) by using metal-organic frameworks (MOFs) as catalysts. Four types of thermally stable MOFs (MIL-47 (V), MIL-53 (Al), MIL-101 (Cr), and UiO-6
- Zhang, Zhiguo,Chen, Jingwen,Bao, Zongbi,Chang, Ganggang,Xing, Huabin,Ren, Qilong
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p. 79355 - 79360
(2015/10/05)
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- Enantioselective cyanosilylation of aldehydes catalyzed by novel camphor derived Schiff bases-titanium(IV) complexes
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Five tridentate Schiff bases have been prepared from (1R,2S,3R,4S)-3-amino- 1,7,7-trimethylbicyclo[2.2.1]heptan-2-ol and salicylaldehydes. X-ray structure investigation revealed differences in their molecular conformation, and their titanium(IV) complexes
- B?ocka, Ewelina,Bosiak, Mariusz J.,We?niak, Miros?aw,Ludwiczak, Agnieszka,Wojtczak, Andrzej
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p. 554 - 562
(2014/05/06)
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- The application of spontaneous flocculation for the preparation of lanthanide-containing polyoxometalates intercalated layered double hydroxides: highly efficient heterogeneous catalysts for cyanosilylation
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The lanthanide-containing polyoxometalates (POMs) have been intercalated into layered double hydroxides (LDHs) successfully through the spontaneous flocculation method, resulting in the formation of new heterogeneous LDHs–POMs catalysts Mg3Al–L
- Jia, Yueqing,Song, Yu-Fei,Zhao, Shen
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p. 172 - 180
(2020/12/07)
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- Tri-lacunary polyoxometalates of Na8H[PW9O 34] as heterogeneous Lewis base catalysts for Knoevenagel condensation, cyanosilylation and the synthesis of benzoxazole derivatives
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We reported for the first time the development of tri-lacunary polyoxometalates (POMs) of Na8H[A-PW9O34] ·7H2O and Na8H[B-PW9O 34]·19H2O (Na-A-PW9 and Na-B-PW 9) as highly selective and efficient heterogeneous Lewis base catalysts for Knoevenagel condensation, cyanosilylation of various aldehydes and ketones and the synthesis of benzoxazole derivatives at 25 C under mild conditions. Since both Na-A-PW9 and Na-B-PW9 display no characteristic porosity, it is proposed that the catalytic reactions proceed not only on the surface and interface, but also in the bulk phase. The catalysts can be easily recovered and reused for at least six times without obvious decrease of catalytic activities and the structures of the catalysts remain unchanged after recycling. The easy preparation, high efficiency, reusability of the heterogeneous catalysts of Na-A-PW9 and Na-B-PW9 exhibit great potential for further application.
- Zhao, Shen,Chen, Yang,Song, Yu-Fei
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p. 140 - 146
(2014/03/21)
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- Dismantling the salen framework: Design of new asymmetric silylcyanation catalysts
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A series of novel chiral phenoxyimine Al(iii) complexes catalyzes asymmetric addition of SiMe3CN to a broad range of aldehydes with high yields and good to excellent enantioselectivities in the presence of a Lewis base.
- Ternel, Jeremy,Roussel, Pascal,Agbossou-Niedercorn, Francine,Gauvin, Regis M.
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p. 580 - 583
(2013/03/28)
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- Efficient synthesis of cyanohydrin trimethylsilyl ethers via 1,2-chemoselective cyanosilylation of carbonyls
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Here we report a sustainable protocol for the cyanosilylation of carbonyl compounds 1a-g and 3a-m using trimethylsilyl cyanide and triphenylphosphine supported on polystyrene as a catalyst under solvent-free conditions. It has been shown that a small amou
- Strappaveccia, Giacomo,Lanari, Daniela,Gelman, Dmitri,Pizzo, Ferdinando,Rosati, Ornelio,Curini, Massimo,Vaccaro, Luigi
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p. 199 - 204
(2013/02/23)
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- Asymmetric cyanohydrin synthesis using an aluminium(salan) complex
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The asymmetric addition of trimethylsilyl cyanide to aldehydes catalysed by chiral metal(salan) complexes has been investigated. Salan complexes of titanium and vanadium displayed only low catalytic activity, but a bimetallic aluminium(salan) complex gave
- North, Michael,Stewart, Emma L.,Young, Carl
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p. 1218 - 1225,8
(2020/09/09)
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- Polystyrene-supported TBD as an efficient and reusable organocatalyst for cyanosilylation of aldehydes, ketones, and imines
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Polystyrene-supported TBD (PS-TBD) catalyzes cyanosilylation of both aldehydes and ketones using TMSCN to give the corresponding products in high yields. Imines were also converted into the desired α-cyanoanimes under the same conditions. PS-TBD was easil
- Matsukawa, Satoru,Fujikawa, Syohei
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supporting information; experimental part
p. 1075 - 1077
(2012/04/17)
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- Catalytic asymmetric synthesis of secondary nitriles via stereoconvergent negishi arylations and alkenylations of racemic α-bromonitriles
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The first method for the stereoconvergent cross-coupling of racemic α-halonitriles is described, specifically, nickel-catalyzed Negishi arylations and alkenylations that furnish an array of enantioenriched α-arylnitriles and allylic nitriles, respectively. Noteworthy features of this investigation include: the highly enantioselective synthesis of α-alkyl-α-aryl nitriles that bear secondary α-alkyl substituents; the first examples of the use of alkenylzinc reagents in stereoconvergent Negishi reactions of alkyl electrophiles; demonstration of the utility of a new family of ligands for asymmetric Negishi cross-couplings (a bidentate bis(oxazoline), rather than a tridentate pybox); in the case of arylzinc reagents, carbon-carbon bond formation at a remarkably low temperature (-78 °C), the lowest reported to date for an enantioselective cross-coupling of an alkyl electrophile; a mechanistic dichotomy between Negishi reactions of an unactivated versus an activated secondary alkyl bromide.
- Choi, Junwon,Fu, Gregory C.
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supporting information; experimental part
p. 9102 - 9105
(2012/07/13)
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- Perfectly green organocatalysis: Quaternary ammonium base triggered cyanosilylation of aldehydes
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Quaternary ammonium bases, such as aqueous (CH3)4NOH, were found to be an extraordinarily efficient catalyst for cyanosilylation of aldehydes. The addition reaction of trimethylsilyl cyanide (TMSCN) to equivalent aldehydes could proceed smoothly with turnover frequency (TOF) up to 3000000 h-1 and in near 100% yield under solvent-free conditions. These organic catalysts also tolerated various aldehydes including aromatic, aliphatic and α,β-unsaturated aldehydes. This process perfectly conforms to the features of green chemistry: no waste regarding side-products and unconverted reactants, solvent-free, excellent catalytic activity, and no requirement for separation.
- Wen, Yeqian,Liang, Mengwei,Wang, Yiming,Ren, Weimin,Lue, Xiaobing
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p. 2109 - 2114
(2012/11/07)
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- Cooperative thiourea-Bronsted acid organocatalysis: Enantioselective cyanosilylation of aldehydes with TMSCN
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We report a new thiourea - Bronsted acid cooperative catalytic system for the enantioselective cyanosilylation of aldehydes with yields up to 90% and enantioselectivities up to 88%. The addition of an achiral acid was found to be crucial for high asymmetric induction. Mechanistic investigations using a combination of NMR, ESI-MS, and density functional theory computations (including solvent corrections) at the M06/6-31G(d,p) level of theory suggest that the key catalytic species results from the cooperative interaction of bifunctional thioureas and an achiral acid that form well-defined chiral hydrogen-bonding environments.
- Zhang, Zhiguo,Lippert, Katharina M.,Hausmann, Heike,Kotke, Mike,Schreiner, Peter R.
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experimental part
p. 9764 - 9776
(2012/01/03)
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- An efficient titanium catalyst for enantioselective cyanation of aldehydes: Cooperative catalysis
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(Figure Presented) Two-in-one: The integration of two salen/ Ti=O units into one molecule allows the enantioselective cyanation of aldehydes to afford the enantioenriched natural or nonnatural cyanohydrin derivatives with turnover numbers of 1960-172000 a
- Zhang, Zhipeng,Wang, Zheng,Zhang, Ruzhou,Ding, Kuiling
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supporting information; experimental part
p. 6746 - 6750
(2010/12/24)
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- Kinetics and mechanism of vanadium catalysed asymmetric cyanohydrin synthesis in propylene carbonate
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Propylene carbonate can be used as a green solvent for the asymmetric synthesis of cyanohydrin trimethylsilyl ethers from aldehydes and trimethylsilyl cyanide catalysed by VO(salen)NCS, though reactions are slower in this solvent than the corresponding re
- North, Michael,Omedes-Pujol, Marta
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experimental part
p. 1043 - 1055
(2011/03/22)
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- Facile preparation of 1,2-diketones
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Easily accessible lead-like libraries of heterocyclic molecules useful for high-throughput screening are of continuous interest to the pharmaceutical industry. A number of drug-like libraries are derived from aromatic 1,2-diketones; however, nonsymmetrical 1,2-diketones are challenging to prepare. This communication describes a simple and practical synthesis of 1,2-diketones based on a controlled cross benzoin-like condensation reaction. Copyright Taylor & Francis Group, LLC.
- Nowak, Pawel,Malwitz, David,Cole, Derek C.
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experimental part
p. 2164 - 2171
(2010/08/13)
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- A bimetallic aluminium(salen) complex for asymmetric cyanohydrin synthesis
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In the presence of a phosphine oxide cocatalyst, a bimetallic aluminium(salen) complex was found to catalyse the asymmetric addition of trimethylsilyl cyanide to aldehydes. Under optimised conditions, enantioselectivities of 53-96% were obtained using 2 m
- North, Michael,Williamson, Courtney
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experimental part
p. 3249 - 3252
(2009/08/17)
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- Catalytic, asymmetric cyanohydrin synthesis in propylene carbonate
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Propylene carbonate can be used as a green solvent for asymmetric cyanohydrin synthesis catalyzed by VO(salen)NCS. A range of 10 aromatic and aliphatic aldehydes gave high enantioselectivities (up to 93%) and conversions (up to 100%) in reactions carried
- North, Michael,Omedes-Pujol, Marta
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experimental part
p. 4452 - 4454
(2009/12/01)
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- Tris(2,4,6-trimethoxyphenyl)phosphine (TTMPP): Efficient catalysts for the cyanosilylation and cyanocarbonation of aldehydes and ketones
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A variety of aldehydes and ketones were transformed to their corresponding cyanohydrin silyl ethers in good to excellent yields in the presence of 1-5 mol% of tris(2,4,6-trimethoxyphenyl)phosphine (TTMPP). Cyanohydrin carbonates were also readily prepared using 5-10 mol% of TTMPP as an organocatalyst.
- Matsukawa, Satoru,Sekine, Izumi,Iitsuka, Ayumi
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experimental part
p. 3353 - 3359
(2009/12/26)
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- Dibutyltin dibromide-catalyzed trimethylsilylcyanation of aldehydes and imines
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Dibutyltin dibromide efficiently catalyzes addition of tri-methylsilyl cyanide to aldehydes and aldimines. Various tri-methylsilylated cyanohydrins and α-aminonitriles are obtained in moderate to high yield by this method. Copyright
- Yanagisawa, Akira,Matsumoto, Takuya,Arai, Takayoshi,Yoshida, Kazuhiro
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scheme or table
p. 336 - 337
(2010/01/16)
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- Enantioselective silylcyanation of aldehydes and ketones by a titanium catalyst prepared from a partially hydrolyzed titanium alkoxide and a Schiff base ligand
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In the presence of small amount (0.2-1.0 mol%) of a titanium complex catalyst prepared from a partially hydrolyzed titanium alkoxide and an optically active tridentate Schiff base ligand, the enantioselective silylcyanation of aldehydes and ketones procee
- Yoshinaga, Kazuhiko,Nagata, Takushi
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supporting information; experimental part
p. 1495 - 1498
(2011/02/24)
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- [Ru(phgly)2(binap)]/Li2CO3: A Highly Active, Robust, and Enantioselective Catalyst for the Cyanosilylation of Aldehydes
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The right combination: A series of aromatic, heteroaromatic, aliphatic, and α,β-unsaturated aldehydes can be converted into the desired silylated cyanohydrins by reaction with (CH3)3SiCN and a catalyst system consisting of the combination of a chiral ruthenium complex and Li2CO3 (see scheme). The reaction is highly enantioselective and affords the R products with up to 98% ee within 24 h at a substrate-tocatalyst ratio of 10000:1. (Chemical Equation Presented).
- Kurono, Nobuhito,Arai, Kenta,Uemura, Masato,Ohkuma, Takeshi
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supporting information; experimental part
p. 6643 - 6646
(2009/03/12)
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- Titanium(IV)(salen) and yanadium(V)(salen) complexes derived from C 2- and C1-symmetric diamines for asymmetric cyanohydrin synthesis
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Titanium and vanadium salen complexes have been prepared from C 2- and C1-symmetric acyclic diamines. All of the complexes catalysed the asymmetric addition of trimethylsilyl cyanide to benzaldehyde and the sense of asymmetric induction was determined by the nature of the substituents. The vanadium complex of a valine-derived diamine gave good results with a range of aromatic and aliphatic aldehydes. Georg Thieme Verlag Stuttgart.
- Belokon', Yuri N.,Hunt, Jamie,North, Michael
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experimental part
p. 2150 - 2154
(2009/05/07)
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- Asymmetric catalysis of carbon-carbon bond forming reactions using amino acid-derived C1-symmetrical salen ligands
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Four amino acids (alanine, valine, phenylalanine and phenylglycine) have been converted into C1-symmetrical salen ligands and complexed to titanium, vanadium, copper and cobalt. The resulting complexes have been used as asymmetric catalysts for asymmetric cyanohydrin synthesis, asymmetric Strecker reactions, asymmetric synthesis of α-methyl amino acids and asymmetric Darzens condensations. Satisfactory levels of asymmetric induction were obtained from reactions in which the (salen)metal complex acts as a chiral Lewis acid, but low levels of asymmetric induction were obtained from reactions carried out under solid-liquid phase-transfer conditions.
- Belokon, Yuri N.,Hunt, Jamie,North, Michael
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experimental part
p. 2804 - 2815
(2009/06/28)
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- Remarkable acceleration of cyanosilylation by the mesoporous Al-MCM-41 catalyst
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The presence of the heterogeneous mesoporous Al-MCM-41 catalyst remarkably accelerated the cyanosilylation of various aldehydes and ketones with trialkylsilyl cyanide, giving the corresponding cyanohydrin silyl ethers in quantitative yields under mild reaction conditions. The Royal Society of Chemistry.
- Iwanami, Katsuyuki,Choi, Jun-Chul,Lu, Baowang,Sakakura, Toshiyasu,Yasuda, Hiroyuki
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p. 1002 - 1004
(2008/09/21)
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- Cyanosilylation of aldehydes and ketones catalyzed by nanocrystalline magnesium oxide
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Cyanosilylation of various aldehydes and ketones with TMSCN proceeded smoothly under mild conditions to give the corresponding cyanohydrin trimethylsilyl ethers in the presence of nanocrystalline magnesium oxide. The cyanohydrin trimethylsilyl ethers of aldehydes produced cyanohydrins in good to high yields on treatment with 2 N HCl. 29Si NMR spectral evidence proved that the reaction proceeds through the hypervalent silicate species by coordination to O2-/O- (Lewis basic site) of nanocrystalline magnesium oxide. Copyright Taylor & Francis Group, LLC.
- Lakshmi Kantam,Mahendar, Koosam,Sreedhar, Bojja,Vijay Kumar,Choudary
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experimental part
p. 3919 - 3936
(2009/04/11)
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- Niobium fluoride (NbF5): A highly efficient catalyst for solvent-free cyanosilylation of aldehydes
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An efficient method for the addition of trimethylsilylcyanide (TMSCN) to aldehydes using dispersed NbF5 as the catalyst is described. Cyano transfer from TMSCN to aldehydes occurs within 10 minutes at room temperature in the presence of 0.5 mol
- Sung, Soo Kim,Rajagopal, Gurusamy
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p. 215 - 218
(2007/10/03)
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- Enantioselective cyanosilylation of aldehydes catalysed by a diastereomeric mixture of atropisomeric thioureas
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New bifunctional atropisomeric thioureas 1 were synthesised and tested as both a mixture of diastereomers (aR/aS)-(R,R)-1 and as single diastereomers (aR)-(R,R)-1 and (aR)-(S,S)-1, in the organocatalysed, enantioselective, cyanosilylation of a range of al
- Steele, Rebecca M.,Monti, Chiara,Gennari, Cesare,Piarulli, Umberto,Andreoli, Federico,Vanthuyne, Nicolas,Roussel, Christian
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p. 999 - 1006
(2007/10/03)
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- Cyanosilylation of aldehydes catalyzed by N-heterocyclic carbenes
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N-Heterocyclic carbenes produced in situ from salts of imidazolium, benzimidazolium, pyrido[1,2-c]imidazolium, imidazolinium, thiazolium, and triazolium catalyze the addition of trimethylsilylcyanide to aldehydes to yield cyanohydrin trimethylsilyl ethers. The use of C2-symmetric imidazolidenyl carbene derived from (R,R)-1,3-bis[(1-naphthyl)ethyl]imidazolium chloride led to enantioselective cyanosilylation.
- Suzuki, Yumiko,Bakar, M.D., Abu,Muramatsu, Kazuyuki,Sato, Masayuki
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p. 4227 - 4231
(2007/10/03)
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- Chiral Pt(II)/Pd(II) pincer complexes that show C-H?Cl hydrogen bonding: Synthesis and applications to catalytic asymmetric aldol and silylcyanation reactions
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A chiral C2-symmetric NCN ligand, (5R,7R)-1,3-bis(6,6-dimethyl-5,6,7,8-tetrahydro-5,7-methanoquinolin-2-yl)benzene has been synthesized. A direct cyclometalation of this ligand with K2MCl4 (M = Pt, Pd) in dry acetic acid offered the corresponding pincer complexes, [(5R,7R)-1,3-bis(6,6-dimethyl-5,6,7,8-tetrahydro-5,7-methanoquinolin-2-yl)phenyl]platinum(II) chloride 5a and its palladium(II) analogue 5b. The Pt(II) and Pd(II) complexes 5 were characterized by NMR spectroscopy, and X-ray crystal structure analysis was done for the Pt(II) complex. The NMR data for both the complexes and X-ray crystal structural data for the chloro-Pt(II) complex indicate the existence of intramolecular C-H?Cl hydrogen bonding both in solution and in solid states. Chloride abstraction from 5a by treatment with silver triflate resulted in the corresponding triflate complex 6a, which generates the corresponding cationic aqua complex 7a in the presence of water molecules. The Pt(II) complex 6a/7a was used as asymmetric catalyst in the aldol reaction between methyl isocyanoacetate and aldehydes and also in the silylcyanation of aldehydes.
- Yoon, Myeong Sik,Ramesh, Rengan,Kim, Jeongryul,Ryu, Dowook,Ahn, Kyo Han
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p. 5939 - 5946
(2007/10/03)
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- An N-heterocyclic carbene as a nucleophilic catalyst for cyanosilylation of aldehydes
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The first method for cyanosilylation of aldehydes with trimethylsilyl cyanide in the presence of the N-heterocyclic carbene prepared from 1,3-bis(2,4,6-trimethylphenyl)imidazolium chloride and potassium tert-butoxide, as a nucleophilic catalyst, is described. Georg Thieme Verlag Stuttgart.
- Fukuda, Yoshimasa,Maeda, Yuka,Ishii, Satoru,Kondo, Kazuhiro,Aoyama, Toyohiko
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p. 589 - 590
(2007/10/03)
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- Synthesis of the bifunctional BINOL ligands and their applications in the asymmetric additions to carbonyl compounds
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Efficient one-step syntheses of the bifunctional BINOL and H8BINOL ligands (S)-6 and (S)-8 have been developed from the reaction of BINOL and H8BINOL with morpholinomethanol, respectively. The X-ray analyses of these compounds have revealed their structural similarity and difference. The bifunctional H8BINOL (S)-8 is found to be highly enantioselective for the reaction of diphenylzinc with many aliphatic and aromatic aldehydes and especially is the most enantioselective catalyst for linear aliphatic aldehydes. Unlike other catalysts developed for the diphenylzinc addition which often require the addition of a significant amount of diethylzinc with cooling (or heating) the reaction mixture in order to achieve high enantioselectivity, using (S)-8 needs no additive and gives excellent results at room temperature. (S)-8 in combination with diethylzinc and Ti(OiPr)4 can catalyze the highly enantioselective phenylacetylene addition to aromatic aldehydes. It can also promote the phenylacetylene addition to acetophenone at room temperature though the enantioselectivity is not very high yet. Without using Ti(OiPr)4 and a Lewis base additive, (S)-8 in combination with diethylzinc can catalyze the reaction of methyl propiolate with an aldehyde to form the highly functional γ-hydroxy-α,β-acetylenic esters except that the enantioselectivity is low at this stage. The bifunctional BINOL ligand (S)-6 in combination with Me2AlCl is found to be a highly enantioselective catalyst for the addition of TMSCN to both aromatic and aliphatic aldehydes.
- Qin, Ying-Chuan,Liu, Lan,Sabat, Michal,Pu, Lin
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p. 9335 - 9348
(2007/10/03)
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- Guanidine-catalyzed asymmetric trimethylsilylcyanation of carbonyl compounds
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Several kinds of modified guanidines were applied to the trimethylsilylcyanation of 3-phenylpropanal, cylohexanecarboxaldehyde, pivalaldehyde, and 4-phenyl-2-butanone. Good to moderate enantioselectivity was obtained, even on a ketonic substrate, when a C
- Kitani, Yukari,Kumamoto, Takuya,Isobe, Toshio,Fukuda, Keiko,Ishikawa, Tsutomu
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p. 1653 - 1658
(2007/10/03)
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- Lithium chloride: An active and simple catalyst for cyanosilylation of aldehydes and ketones
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LiCl acts as a highly effective catalyst for cyanosilylation of various aldehydes and ketones to the corresponding silylated cyanohydrins. The reaction proceeds smoothly with a substrate/catalyst molar ratio of 100-100 000 at 20-25 °C under solvent-free conditions. α,β-Unsaturated aldehydes are completely converted to the 1,2-adducts. The cyanation products can be isolated by direct distillation of the reaction mixture.
- Kurono, Nobuhito,Yamaguchi, Masayo,Suzuki, Ken,Ohkuma, Takeshi
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p. 6530 - 6532
(2007/10/03)
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- N-methylmorpholine N-oxide: A rare nonmetallic catalyst for the most efficient silylcyanation of aldehydes
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An efficient method of addition of trimethylsilyl cyanide (TMSCN) to aldehydes by employing N-methylmorpholine N-oxide (NMO) alone as the catalyst has been described. Most of aromatic, aliphatic, cyclic, and heterocyclic aldehydes have been converted into
- Kim, Sung Soo,Rajagopal, Gurusamy,Kim, Dong Won,Song, Dae Ho
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p. 2973 - 2980
(2007/10/03)
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- Potassium exchanged zirconium hydrogen phosphate as heterogeneous catalyst in cyanosilylation of carbonyl compounds
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Layered zirconium hydrogen phosphate exchanged with potassium ion was found to be an efficient heterogeneous catalyst for cyanosilylation of carbonyl compounds.
- Curini, Massimo,Epifano, Francesco,Marcotullio, Maria Carla,Rosati, Ornelio,Rossi, Monia
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p. 315 - 316
(2007/10/03)
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