51096-49-2Relevant academic research and scientific papers
Synthesis, characterization and catalytic application of Bi2S3 microspheres for Suzuki-Miyaura cross-coupling reaction and chemoselective ring opening of epoxides
Ghorbani-Choghamarani, Arash,Taherinia, Zahra
, (2020/11/20)
Bismuth sulfide (Bi2S3) prepared using L-cysteine, which served as both the sulfur source and the directing molecule for the formation of Bi2S3 as heterogeneous catalyst through solvothermal method. The prepared catalyst was examined by various techniques such as XRD, BET, FE-SEM, TEM, and TGA analysis. The results and analysis revealed that bismuth microspheres have better catalytic behavior for the preparation of biphenyl in water as a greenest solvent and for the ring opening of epoxides by nucleophiles including amines, alcohol, and thiol compared to pure Bi(NO3)3. 3H2O under solvent-free condition. Moreover, the novel catalyst could be recovered and reusedat least four times without loss of its catalytic activity.
Amine grafted Fe3O4 immobilized graphene oxide as a recyclable and effectual nanocomposite for the regioselective ring opening reaction
Gupta, Padmini,Garkoti, Charu,Shabir, Javaid,Surabhi,Sah, Digvijay,Mozumdar, Subho
, p. 4013 - 4028 (2021/06/25)
This work describes the synthesis of magnetic graphene oxide (MGO), where iron oxide (Fe3O4) nanoparticles were uniformly deposited over the sheets of the graphene oxide (GO). Further, the introduction of aminopropyltrimethoxysilane (APTMS) on the surface of MGO was successfully done and results in the formation of amine-functionalized magnetic graphene oxide (MGO–NH2). The synthesized heterogeneous magnetic nanocomposite was characterized by numerous physicochemical and morphological techniques such as powder X-ray diffraction, Fourier transform infrared, thermogravimetric analysis, transmission electron microscopy, vibrating sample magnetometer, scanning electron microscopy, CHN analyzer, and energy-dispersive X-ray analysis. The synthesized nanocomposite was proved to be an effectual catalyst in the nucleophilic ring opening reactions of styrene oxide with derivatives of amines under green solvent. The present catalyst displayed good catalytic activity, short reaction time, higher regioselectivity, excellent yields and could be reutilized up to seven catalytic rounds with no substantial loss in its activity. The excellent properties of the catalyst are due to the dual character of acidic groups (existence of carboxyl groups on the sheet edges) and basic groups (amine groups anchored on the surface of GO). On completion of the reaction, the prepared nanocomposite could be effortlessly recovered from the reaction mixture by utilizing an external magnet, owing to the ferromagnetic property of Fe3O4. Graphical Abstract: [Figure not available: see fulltext.].
Highly regioselective ring-opening of epoxides with amines: A metal- A nd solvent-free protocol for the synthesis of β-amino alcohols
Li, Dong,Wang, Jing,Yu, Shibo,Ye, Silei,Zou, Wenjie,Zhang, Hongbin,Chen, Jingbo
supporting information, p. 2256 - 2259 (2020/03/04)
We herein report a metal- A nd solvent-free acetic acid-mediated ring-opening reaction of epoxides with amines. This process provides β-amino alcohols in high yields with excellent regioselectivity. Importantly, this epoxide ring-opening protocol can be used for the introduction of amines in natural products during late-stage transformations.
M-Type SrFe12O19Ferrite: An Efficient Catalyst for the Synthesis of Amino Alcohols under Solvent-Free Conditions
Laayati, Mouhsine,Hasnaoui, Ali,Abdallah, Nayad,Oubaassine, Saadia,Fkhar, Lahcen,Mounkachi, Omar,El Houssame, Soufiane,Ait Ali, Mustapha,El Firdoussi, Larbi
, (2020/08/05)
Magnetically separable strontium hexaferrite SrFe12O19 was prepared using the chemical coprecipitation method, and the nanostructured material was characterized by X-ray diffraction, scanning electron microscopy (SEM), energy-dispersive spectrometry (EDS), and BET analysis. The SEM images showed the homogeneity of the chemical composition of SrFe12O19 and uniform distribution of size and morphology. The pore size of the nanomaterial and its specific area were determined by BET measurements. Strontium hexaferrite SrFe12O19 exhibited a strong magnetic field, which is highly suitable in the heterogeneous catalysis as it can be efficiently separated from the reaction. The magnetic nanocatalyst showed high activity and environmentally benign heterogeneous catalysts for the epoxide ring-opening with amines affording β-amino alcohols under solvent-free conditions. When unsymmetrical epoxides were treated in the presence of aromatics amines, the regioselectivity was influenced by the electronic and steric factors. Total regioselectivity was observed for the reactions performed with aliphatic amines. The magnetically SrFe12O19 nanocatalyst showed excellent recyclability with continuously good catalytic activities after four cycles.
OLIGONUCLEOTIDE AND NUCLEIC ACID SYNTHESIS
-
Page/Page column 124; 125, (2019/08/12)
The present invention relates to methods for the high fidelity synthesis of oligonucleotides and polynucleotides on a solid surface. In particular, the invention relates to methods of synthesising oligonucleotides, polynucleotides, and doublestranded polynucleotides/nucleic acids, such as DNA and XNA, wherein the process comprises thermally controlled deprotection steps at the 5'-OH of previously coupled nucleosides or nucleotides at selected sites on the surface of the substrate.
THERMALLY-CLEAVABLE PROTECTING AND LINKER GROUPS
-
Page/Page column 56; 57, (2018/11/10)
The present invention relates to chemical linkers and protecting groups, compounds and compositions containing the chemical linkers or protecting groups, and intermediates and processes that can be used to prepare them. The chemical linkers and protecting groups are based on pyrrolidine and piperidine activating groups, which undergo intramolecular cyclisation upon heating with release of carbon dioxide, thereby releasing the organic compound from a substrate. In particular, those chemical linkers and protecting groups are useful in the solid phase synthesis of oligonucleotides according to the following representative schemes.
β-amino alcohols and their respective 2-phenyl-N-alkyl aziridines as potential DNA minor groove binders
Vaidergorn, Miguel M.,Carneiro, Zumira A.,Lopes, Carla D.,de Albuquerque, Sérgio,Reis, Felipe C.C.,Nikolaou, Sofia,Mello, Juliana F.R. e,Genesi, Giovani L.,Trossini, Gustavo H.G.,Ganesan,Emery, Flavio S.
, p. 657 - 664 (2018/08/23)
It is known that aziridines and nitrogen mustards exert their biological activities, especially in chemotherapy, via DNA alkylation. The studied scaffold, 2-phenyl-1-aziridine, provides a distinct conformation compared to commonly used aziridines, and the
Visible-Light-Promoted Metal-Free Aerobic Hydroxyazidation of Alkenes
Yang, Bo,Lu, Zhan
, p. 8362 - 8365 (2017/12/08)
A highly efficient visible-light-promoted metal-free aerobic hydroxyazidation of alkenes has been developed. This protocol was operationally simple with broad substrate scope using relatively simple and readily available starting materials, such as alkene
Direct catalytic synthesis of unprotected 2-amino-1-phenylethanols from alkenes by using iron(II) phthalocyanine
Legnani, Luca,Morandi, Bill
supporting information, p. 2248 - 2251 (2016/02/18)
Aryl-substituted amino alcohols are privileged scaffolds in medicinal chemistry and natural products. Herein, we report that an exceptionally simple and inexpensive FeII complex efficiently catalyzes the direct transformation of simple alkenes into unprotected amino alcohols in good yield and perfect regioselectivity. This new catalytic method was applied in the expedient synthesis of bioactive molecules and could be extended to aminoetherification.
Green Regio- and Enantioselective Aminolysis Catalyzed by Graphite and Graphene Oxide under Solvent-Free Conditions
Acocella, Maria Rosaria,D'Urso, Luciana,Maggio, Mario,Guerra, Gaetano
, p. 1915 - 1920 (2016/07/06)
The ring-opening reactions of epoxides with amines were efficiently and regioselectively catalyzed by high-surface-area graphite and graphene oxide under metal-free and solvent-free conditions. For epoxides without aryl groups, catalytic activity was observed only for graphene oxide, and hence, the activity must have been due to its acidic groups. For styrene oxide, instead, graphite and graphene oxide exhibited rather similar catalytic activities, and hence, the activity was mainly due to activation of the electrophilic epoxide by π-stacking interactions with the graphitic π system. The described aminolysis procedure is green and cheap because the catalyst can be recovered and recycled without loss of efficiency. Moreover, these heterogeneous catalysts exert high stereoselective control in the presence of nonracemic epoxides and provide chiral β-amino alcohols with enantiomeric excess values up to 99 %.
