459-45-0Relevant academic research and scientific papers
High-Yield Preparation of Exfoliated 1T-MoS2 with SERS Activity
Er, Engin,Hou, Hui-Lei,Criado, Alejandro,Langer, Judith,M?ller, Marco,Erk, Nevin,Liz-Marzán, Luis M.,Prato, Maurizio
, p. 5725 - 5734 (2019)
Molybdenum disulfide (MoS2), a promising two-dimensional transition-metal dichalcogenide, presents a challenge in the tuning of its optoelectronic and chemical properties. Herein, we demonstrate an efficient route to alter the crystalline structure of MoS2 by chemical exfoliation. Using NaK metal alloys, exfoliated and covalently functionalized MoS2 derivatives were obtained with a high metallic (1T) phase ratio, up to 94.5%. Consequently, exfoliated MoS2 showed a significant surface-enhanced Raman scattering activity toward rhodamine 6G (R6G) and crystal violet, with low detection limits. The versatility of this approach allows the covalent functionalization of MoS2 without relying on edge or basal-plane defects of the structure and preserving the high-ratio 1T phase.
A Radical Chain: Mononuclear “Gold Only” Photocatalysis
Witzel, Sina,Hoffmann, Marvin,Rudolph, Matthias,Rominger, Frank,Dreuw, Andreas,Hashmi, A. Stephen K.
supporting information, p. 581 - 592 (2021/12/06)
We herein report an unprecedented reactivity of mononuclear gold catalysts acting as classical catalysts and at the same time as active partners in a radical chain mechanism, whereby gold is the only catalyst. The mechanism of the photo-induced photosensitizer-free “gold only”-catalyzed cross coupling was studied in detail – experimentally and theoretically – based on the reaction between arylboronic acids and aryldiazonium salts. With a systematic set of stoichiometric experiments under various conditions and analytic methods, we could show that this mechanism is initiated by an aryl radical formed in the presence of blue LEDs and MeOH. This aryl radical enters the catalytic cycle to oxidize gold(I) to gold(II). Single electron transfer from gold(II) to the aryldiazonium salt then gives the cationic gold(III) complex by formation of a chain-supporting aryl radical which then is enabled to start a new cycle by oxidation of gold(I) without the need for irradiation. At least every 432 cycles of the radical chain, a new chain-initiating radical has to restart the radical chain. Eventually, the boronic acid is activated by the BF4? anion to transmetalate to gold(III), and reductive elimination delivers the desired product.
Aqueous and Visible-Light-Promoted C-H (Hetero)arylation of Uracil Derivatives with Diazoniums
Liu, An-Di,Wang, Zhao-Li,Liu, Li,Cheng, Liang
, p. 16434 - 16447 (2021/11/16)
Direct C5 (hetero)arylation of uracil and uridine substrates with (hetero)aryl diazonium salts under photoredox catalysis with blue light was reported. The coupling proceeds efficiently with diazonium salts and heterocycles in good functional group tolerance at room temperature in aqueous solution without transition-metal components. A plausible radical mechanism has been proposed.
Metal-Free Visible-Light Synthesis of Arylsulfonyl Fluorides: Scope and Mechanism
Chelagha, Aida,Khrouz, Lhoussain,Louvel, Dan,Monnereau, Cyrille,Payard, Pierre-Adrien,Rouillon, Jean,Tlili, Anis
supporting information, p. 8704 - 8708 (2021/05/17)
The first metal-free procedure for the synthesis of arylsulfonyl fluorides is reported. Under organo-photoredox conditions, aryl diazonium salts react with a readily available SO2 source (DABSO) to afford the desired product through simple nucleophilic fluorination. The reaction tolerates the presence of both electron-rich and -poor aryls and demonstrated a broad functional group tolerance. To shed the light on the reaction mechanism, several experimental techniques were combined, including fluorescence, NMR, and EPR spectroscopy as well as DFT calculations.
Aryl Diazonium Salts: Powerful Arylating Agents for Catellani-Typeortho-Arylation
Fu, Ying,Guo, Liang-Liang,Zhang, Yu-Xia
supporting information, p. 17437 - 17444 (2021/12/02)
The Catellani reaction provides an efficient synthetic approach to polyfunctionalized arenes. However, the selectiveortho-arylating reagents employed in these reactions have been strictly limited to activated bromoarenes. As demonstrated in this work, aryl diazonium salts bearing both electron-donating and electron-withdrawing substituents, after in situ transformations with KI into the corresponding iodoarenes, were efficient arylating reagents for Catellani typeortho-arylation approaches.
HETEROARYLMETHYLENE DERIVATIVES AS DNA POLYMERASE THETA INHIBITORS
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Paragraph 0243, (2020/08/22)
Disclosed herein are certain acetamido derivatives that are DNA Polymerase Theta (Polθ) inhibitors of Formula (I). Also, disclosed are pharmaceutical compositions comprising such compounds and methods of treating diseases treatable by inhibition of Polθ such as cancer, including homologous recombination (HR) deficient cancers.
RhIII-Catalyzed Synthesis of Highly Substituted 2-Pyridones using Fluorinated Diazomalonate
Das, Debapratim,Sahoo, Gopal,Biswas, Aniruddha,Samanta, Rajarshi
supporting information, p. 360 - 364 (2020/01/25)
A RhIII-catalyzed strategy was developed for the rapid construction of highly substituted 2-pyridone scaffolds using α,β-unsaturated oximes and fluorinated diazomalonate. The reaction proceeds through direct, site-selective alkylation based on migratory insertion and subsequent cyclocondensation. A wide substrate scope with different functional groups was explored. The requirement of fluorinated diazomalonate was explored for this transformation. The developed methodology was further extended with the synthesis of the bioactive compound.
Dual palladium-photoredox catalyzed chemoselective C-H arylation of phenylureas
Babu, Sakamuri Sarath,Shahid,Gopinath, Purushothaman
supporting information, p. 5985 - 5988 (2020/06/04)
A highly chemoselective C-H arylation of phenylureas has been accomplished using dual palladium-photoredox catalysis at room temperature without any additives, base or external oxidants. Regioselective C-H arylation ofN,N'-diaryl substituted unsymmetrical phenylureas has also been accomplished by a careful choice of aryl groups.
Visible-Light-Mediated Ru-Catalyzed Synthesis of 3-(Arylsulfonyl)but-3-enals via Coupling of α-Allenols with Diazonium Salts and Sulfur Dioxide
Herrera, Fernando,Luna, Amparo,Almendros, Pedro
supporting information, p. 9490 - 9494 (2020/12/21)
The first coupling of α-allenols, sulfur dioxide, and arenediazonium salts is presented. The three-component reaction which is promoted by visible light can be easily accomplished using DABSO as a sulfur dioxide surrogate in the presence of a photoredox catalyst. In this manner, a broad range of electron-rich and electron-deficient aryl substituents are well accommodated in the sulfonylation-rearrangement cascade to afford the 2,2-disubstituted 3-(arylsulfonyl)but-3-enals in reasonable yields. Based on control experiments, a radical mechanism which does imply 1,2-aryl migration has been proposed.
Highly Efficient Synthesis of Hindered 3-Azoindoles via Metal-Free C-H Functionalization of Indoles
Guillemard, Lucas,Jacob, Nicolas,Wencel-Delord, Joanna
supporting information, p. 574 - 580 (2020/02/13)
Although 3-azoindoles have recently emerged as an appealing family of photoswitch molecules, the synthesis of such compounds has been poorly covered in the literature. Herein a high-yielding and operationally simple protocol is reported allowing the synthesis of 3-azoindoles, featuring important steric hindrance around the azo motif. Remarkably, this C-H coupling is characterized by excellent atom economy and occurs under metal-free conditions, at room temperature, and within few minutes, delivering the expected products in excellent yields (quantitatively in most of the cases). Accordingly, a library of new molecules, with potential applications as photochromic compounds, is prepared.
