85807-85-8Relevant academic research and scientific papers
Termination of living anionic polymerizations using chlorosilane derivatives. A general synthetic methodology for the synthesis of end-functionalized polymers
Peters,Belu,Linton,Dupray,Meyer,DeSimone
, p. 3380 - 3388 (1995)
The transformation of living polymer chain ends is the most widely used technique to synthesize end-functionalized polymeric materials. Herein we report the development of a new synthetic methodology which is able to give very high degrees of functionalization to living anionic polymer chains. This methodology is based on termination reactions with chlorosilane derivatives containing protected functional groups and is described with particular emphasis on the introduction of primary aliphatic amines and primary emphasis on the introduction of primary aliphatic amines and primary aliphatic alcohols. The extent of functionalization was verified by using conventional techniques such as gel permeation chromatography (GPC), end group titration, multinuclear magnetic resonance spectroscopy, and TLC, but was also examined by using time-of-flight secondary ion mass spectrometry (TOF-SIMS). The usefulness of these materials for construction of supramolecular assemblies is illustrated by the coupling of the polymeric amine to [Ru(bpy)2(4-CH34′-CO2Hbpy)]-(PF6)2 (bpy - 2,2′-bipyridine).
Micellar Catalysis for Sustainable Hydroformylation
Calamante, Massimo,Dei, Filippo,Maramai, Samuele,Migliorini, Francesca,Petricci, Elena
, p. 2794 - 2806 (2021/05/03)
It is here reported a fully sustainable and generally applicable protocol for the regioselective hydroformylation of terminal alkenes, using cheap commercially available catalysts and ligands, in mild reaction conditions (70 °C, 9 bar, 40 min). The process can take advantages from both micellar catalysis and microwave irradiation to obtain the linear aldehydes as the major or sole regioisomers in good to high yields. The substrate scope is largely explored as well as the application of hydroformylation in tandem with intramolecular hemiacetalization thus demonstrating the compatibility with a broad variety of functional groups. The reaction is efficient even in large scale and the catalyst and micellar water phase can be reused at least 5 times without any impact in reaction yields. The efficiency and sustainability of this protocol is strictly related to the in situ transformation of the aldehyde into the corresponding Bertagnini's salt that precipitates in the reaction mixture avoiding organic solvent mediated purification steps to obtain the final aldehydes as pure compounds.
Branch-Selective Hydroarylation: Iodoarene-Olefin Cross-Coupling
Green, Samantha A.,Matos, Jeishla L. M.,Yagi, Akiko,Shenvi, Ryan A.
supporting information, p. 12779 - 12782 (2016/10/13)
A combination of cobalt and nickel catalytic cycles enables a highly branch-selective (Markovnikov) olefin hydroarylation. Radical cyclization and ring scission experiments are consistent with hydrogen atom transfer (HAT) generation of a carbon-centered radical that leads to engagement of a nickel cycle.
2-(1-HETEROARYLPIPERAZIN-4-YL)METHYL-1,4-BENZODIOXANE DERIVATIVES AS ALPHA2C ANTAGONISTS
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Page/Page column 26, (2016/12/22)
Compounds of formula I (formula I), wherein A is an optionally substituted five-membered unsaturated heterocyclic ring containing 1, 2 or 3 N, O or S ring heteroatom(s) exhibit alpha2C antagonistic activity and are thus useful for the treatment of diseases or conditions of the peripheric or central nervous system.
Enantioselective Hydroformylation of 1-Alkenes with Commercial Ph-BPE Ligand
Yu, Zhiyong,Eno, Meredith S.,Annis, Alexandra H.,Morken, James P.
supporting information, p. 3264 - 3267 (2015/07/15)
A rhodium complex, in conjunction with commercially available Ph-BPE ligand, catalyzes the branch-selective asymmetric hydroformylation of 1-alkenes and rapidly generates α-chiral aldehydes. A wide range of terminal olefins including 1-dodecene were examined, and all delivered high enantioselectivity (up to 98:2 er) as well as good branch:linear ratios (up to 15:1). (Chemical Equation Presented).
Preparation of nano silica supported sodium hydrogen sulfate: As an efficient catalyst for the trimethyl, triethyl and t-butyldimethyl silylations of aliphatic and aromatic alcohols in solution and under solvent-free conditions
Abri, Abdolreza,Ranjdar, Somayeh
, p. 929 - 934 (2014/10/16)
Nano silica supported sodium hydrogen sulfate 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.
Synthesis of (+)-discodermolide by catalytic stereoselective borylation reactions
Yu, Zhiyong,Ely, Robert J.,Morken, James P.
supporting information, p. 9632 - 9636 (2014/10/15)
The marine natural product (+)-discodermolide was first isolated in 1990 and, to this day, remains a compelling synthesis target. Not only does the compound possess fascinating biological activity, but it also presents an opportunity to test current methods for chemical synthesis and provides an inspiration for new reaction development. A new synthesis of discodermolide employs a previously undisclosed stereoselective catalytic diene hydroboration and also establishes a strategy for the alkylation of chiral enolates. Furthermore, this synthesis of discodermolide provides the first examples of the asymmetric 1,4-diboration of dienes and borylative diene-aldehyde couplings in complex-molecule synthesis. Borylation-based synthesis: The development of a strategy for stereocontrol in catalytic diene hydroboration enables the synthesis of a critical building block for the assembly of (+)-discodermolide. Combined with asymmetric catalytic diboration, hydroformylation, and borylative aldehyde-diene coupling reactions, (+)-discodermolide could then be prepared from simple hydrocarbon-based building blocks.
Synthesis of acylsilanes via nickel-catalyzed reactions of α-hydroxyallylsilanes
Reddy, Gangireddy PavanKumar,Reddy, J. Satyanarayana,Das, Saibal,Roisnel, Thierry,Yadav, Jhillu S.,Chandrasekhar, Srivari,Gree, Rene
supporting information, p. 1524 - 1527 (2013/06/27)
The redox isomerization processes and tandem isomerization-aldolization reactions, mediated by nickel catalysts, offer new versatile entries to acylsilanes. For the second reaction, high diastereoselectivities, up to 98:2, have been obtained with bulky substituents on silicon.
DYE COMPOSITIONS, METHODS OF PREPARATION, CONJUGATES THEREOF, AND METHODS OF USE
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Paragraph 0168; 0169, (2013/07/31)
Dye compounds of the formula (1) wherein A is a protective agent group that has a characteristic of modifying the singlet-triplet occupancy of the shown cyanine moiety, and M is a reactive crosslinking group or a group that can be converted to a reactive crosslinking group. Methods for synthesizing the dye compounds and applications for their use are also described.
A mild and highly efficient method for the preparation of silyl ethers using Fe(HSO4)3/Et3N by chlorosilanes
Abri, Abdolreza,Assadi, Mohammad Galeh,Pourreza, Samira
, p. 1449 - 1454 (2013/03/13)
Avery efficient and mild procedure for preparation of silyl ethers from benzylic, allylic, propargilic alcohols, phenols, naphtoles and some of phenolic drugs with trimethylsilylchloride (TMSCl), triethylsilylchloride (TESCl) and t-buthyldimethylsilyl chloride (TDSCl) ethers in the presence of Fe(HSO 4)3/Et3N in roomtemperature in excellent yields is reported. This procedure also allows the excellent selectivity for silylation of alcohols and phenols.
