13360-81-1Relevant articles and documents
Heterogenization of ferrocene palladacycle catalysts on ROMP-derived monolithic supports and application to a Michael addition
Sudheendran, Mavila,Eitel, Simon H.,Naumann, Stefan,Buchmeiser, Michael R.,Peters, Ren
, p. 5597 - 5607 (2014)
The anchoring of well-defined molecular catalysts on a surface is an attractive strategy to develop sustainable catalytic processes. This article describes the first syntheses of monolith-supported ferrocene palladacycle catalysts. Monolithic supports were prepared via ring-opening metathesis polymerization (ROMP) using the 1st generation Grubbs catalyst . Fluorinated carboxylates were surface-grafted utilizing living Ru-termini. The immobilization of the palladacycles onto the monolithic support was accomplished by ligand substitution on the fluorinated carboxylates of the graft polymer. An investigation of these supported catalysts on the efficiency and reusability under different reaction conditions in a direct Michael addition generating a quaternary C-atom is reported. Whereas stereoselectivity was found to be significantly lower than in a comparable homogeneous system, Pd-leaching was not detected in all analyzed samples indicating a permanently immobilized catalyst system. This journal is
Rational design of a new chiral Lewis acid catalyst for enantioselective Diels-Alder reaction: Optically active 2-dichloroboryl-1,1′-binaphthyl
Ishihara, Kazuaki,Inanaga, Kazato,Kondo, Shoichi,Funahashi, Miyuki,Yamamoto, Hisashi
, p. 1053 - 1056 (1998)
A novel chiral aryldichloroborane catalyst bearing binaphthyl skeletons with axial chirality was developed as an asymmetric catalyst for the Diels-Alder reaction of dienes and α,β-unsaturated esters, and could be reused as the corresponding boronic acid. In addition, a new convenient method for preparing arylboronic acids from aryl alcohols is described.
Exploring the Potential of Norbornene-Modified Mannosamine Derivatives for Metabolic Glycoengineering
Sp?te, Anne-Katrin,Dold, Jeremias E. G. A.,Batroff, Ellen,Schart, Verena F.,Wieland, Daniel E.,Baudendistel, Oliver R.,Wittmann, Valentin
, p. 1374 - 1383 (2016)
Metabolic glycoengineering (MGE) allows the introduction of unnaturally modified carbohydrates into cellular glycans and their visualization through bioorthogonal ligation. Alkenes, for example, have been used as reporters that can react through inverse-electron-demand Diels–Alder cycloaddition with tetrazines. Earlier, norbornenes were shown to be suitable dienophiles; however, they had not previously been applied for MGE. We synthesized two norbornene-modified mannosamine derivatives that differ in the stereochemistry at the norbornene (exo/endo linkage). Kinetic investigations revealed that the exo derivative reacts more than twice as rapidly as the endo derivative. Through derivatization with 1,2-diamino-4,5-methylenedioxybenzene (DMB) we confirmed that both derivatives are accepted by cells and incorporated after conversion to a sialic acid. In further MGE experiments the incorporated sugars were ligated to a fluorophore and visualized through confocal fluorescence microscopy and flow cytometry.
Approach Matters: The Kinetics of Interfacial Inverse-Electron Demand Diels–Alder Reactions
Sen, Rickdeb,Gahtory, Digvijay,Escorihuela, Jorge,Firet, Judith,Pujari, Sidharam P.,Zuilhof, Han
, p. 13015 - 13022 (2017)
Rapid and quantitative click functionalization of surfaces remains an interesting challenge in surface chemistry. In this regard, inverse electron demand Diels–Alder (IEDDA) reactions represent a promising metal-free candidate. Herein, we reveal quantitative surface functionalization within 15 min. Furthermore, we report the comprehensive effects of substrate stereochemistry, surrounding microenvironment and substrate order on the reaction kinetics as obtained by surface-bound mass spectrometry (DART-HRMS).
Method for preparing single-configuration C-2-position-monosubstituted norbornene derivative
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Paragraph 0041-0042, (2021/07/01)
The invention discloses a method for preparing a single-configuration C-2-position-monosubstituted norbornene derivative. The method comprises the following steps of: firstly, preparing exo-isomer enriched exo-isomer mixed 5-norbornene-2-carboxylic ester by taking commercial exo-isomer/endoisomer mixed 5-norbornene-2-carboxylic acid and large-steric-hindrance monohydric alcohol as raw materials; separating 5-norbornene-2-carboxylate with a single configuration through common column chromatography separation or fractionation; and finally, preparing the C-2-position-monosubstituted norbornene derivative with the single configuration from the separated 5-norbornene-2-carboxylate with the single configuration. The raw materials used in the invention are easy to obtain, the preparation process is simple, and the C-2-position-monosubstituted norbornene derivative with high purity (greater than 98%) and single configuration can be obtained.
Fragment-Based Discovery of Pyrazolopyridones as JAK1 Inhibitors with Excellent Subtype Selectivity
Hansen, Bettina Borreschmidt,Jepsen, Tue Heesgaard,Larsen, Mogens,Sindet, Rikke,Vifian, Thomas,Burhardt, Mia N?rreskov,Larsen, Jens,Seitzberg, Jimmi Gerner,Carnerup, Martin A.,Jerre, Anders,M?lck, Christina,Lovato, Paola,Rai, Sanjay,Nasipireddy, Venkatarathnam Reddy,Ritzén, Andreas
, p. 7008 - 7032 (2020/07/28)
Herein, we report the discovery of a series of JAK1-selective kinase inhibitors with high potency and excellent JAK family subtype selectivity. A fragment screening hit 1 with a pyrazolopyridone core and a JAK1 bias was selected as the starting point for our fragment-based lead generation efforts. A two-stage strategy was chosen with the dual aims of improving potency and JAK1 selectivity: Optimization of the lipophilic ribose pocket-targeting substituent was followed by the introduction of a variety of P-loop-targeting functional groups. Combining the best moieties from both stages of the optimization afforded compound 40, which showed excellent potency and selectivity. Metabolism studies in vitro and in vivo together with an in vitro safety evaluation suggest that 40 may be a viable lead compound for the development of highly subtype-selective JAK1 inhibitors.
Structure-Based Design of β5c Selective Inhibitors of Human Constitutive Proteasomes
Xin, Bo-Tao,De Bruin, Gerjan,Huber, Eva M.,Besse, Andrej,Florea, Bogdan I.,Filippov, Dmitri V.,Van Der Marel, Gijsbert A.,Kisselev, Alexei F.,Van Der Stelt, Mario,Driessen, Christoph,Groll, Michael,Overkleeft, Herman S.
supporting information, p. 7177 - 7187 (2016/08/24)
This work reports the development of highly potent and selective inhibitors of the β5c catalytic activity of human constitutive proteasomes. The work describes the design principles, large hydrophobic P3 residue and small hydrophobic P1 residue, that led to the synthesis of a panel of peptide epoxyketones; their evaluation and the selection of the most promising compounds for further analyses. Structure-activity relationships detail how in a logical order the β1c/i, β2c/i, and β5i activities became resistant to inhibition as compounds were diversified stepwise. The most effective compounds were obtained as a mixture of cis- and trans-biscyclohexyl isomers, and enantioselective synthesis resolved this issue. Studies on yeast proteasome structures complexed with some of the compounds provide a rationale for the potency and specificity. Substitution of the N-terminus in the most potent compound for a more soluble equivalent led to a cell-permeable molecule that selectively and efficiently blocks β5c in cells expressing both constitutive proteasomes and immunoproteasomes.
High Tg sulfonated insertion polynorbornene ionomers prepared by catalytic insertion polymerization
Pierre, Florian,Commarieu, Basile,Tavares, Ana C.,Claverie, Jerome
, p. 91 - 97 (2016/02/10)
A simple method to synthesize high Tg sulfonated ionomers based on catalytic insertion polynorbornene is reported. Copolymers of norbornene and 5-methyl alcohol norbornene (endo:exo = 82:18) or 5-methyl bromide norbornene (endo:exo = 86:14) as well as terpolymers of norbornene, 5-methyl alcohol norbornene and 5-hexyl norbornene are prepared using a cationic Pd catalyst. These copolymers are then thioacetylated. Using hydrogen peroxide as oxidant, a sulfonated polynorbornene is obtained. Ionomers containing as much as 30 mol% SO3H and with Tgs above 200 °C are obtained in a four-step procedure of overall 40-75% yield.
Lewis acid mediated asymmetric Diels-Alder reactions of chiral 2-phosphonoacrylates
Zhu, Jia-Liang,Chen, Po-Erh,Huang, Hue-Wen
, p. 23 - 36 (2013/02/23)
2-Phosphonoacrylates containing four chiral alcohol auxiliaries were efficiently prepared and evaluated in Lewis acid mediated Diels-Alder reactions. Under the activation of SnCl4, all reactions performed in CH 2Cl2 at -65 °C exclusively afforded the endo (endo-to-carboxylate) cycloadducts with dr's ranging from 50:50 to >99:1. The best facial selectivity was obtained from the substrate bearing a (-)-phenylmenthyl group, to give adducts as (dr >99:1) or almost as (dr = 99:1) single diastereomers. Detailed strategies for the structural elucidation of the cycloadducts as well as a rationalization of the observed stereoselectivity are described.
LiAlH4-induced reductive dephosphonylation of αα-dialkyl triethyl β-phosphonyl esters: Mechanistic study and synthetic application
Zhu, Jia-Liang,Bau, Jr-Sheng,Shih, You-Cheng
experimental part, p. 863 - 866 (2012/05/20)
Treatment of αα-dialkyl triethyl β-phosphonyl esters with LiAlHin CHlTHF caused the one-pot dephosphonylation and reduction to yield the corresponding primary alcohols bearing a controllable β secondary carbon center. Mechanistic study has revealed that the LiAlHinduced dephosphonylation should occur first with the assistance of the carboxylate group, and the hydrogen source of the resultant new C-H bond is LiAlH. Georg Thieme Verlag Stuttgart . New York.
