Asian Journal of Organic Chemistry最新文献

We investigated how the introduction of substituent at the 9- or 10-position of the 1,8-dichloroanthracene framework affects the horizontal and vertical distortions of the anthracene rings. The 9-substituted anthracenes showed higher distortions than their 10-substituted counterparts due to the steric repulsion with two chloro groups at the peri-positions. The distortion of anthracene framework affected their reactivity. Indeed, 9-substituted anthracenes exhibited higher reactivity to undergo the Diels–Alder reaction with maleic anhydride, which was a result of non-electronic activation.

Cu- and Fe- catalyzed trideuteromethylation reactions using alkylsilyl peroxide as trideuteromethyl radical precursor are reported. The alkylsilyl peroxide was synthesized from acetone-d6 in a three-step sequence, and the reactions with various coupling partners afforded efficiently the corresponding N−CD₃, O−CD₃ and C−CD₃ bond formation products. The radical heptadeuteriopropylation using alkylsilyl peroxide prepared from butyric acid-d7 is also described.

The present article demonstrates the regioselective synthesis, characterization, and biological evaluation of eighteen novel pyrazolo-benzothiazole hybrid molecules 5a–5r. We have utilized β,β-ditosyloxy ketone protocol to synthesize these hybrid molecules. The synthesized compounds were tested for their in-vitro antiproliferative activities using MTT assay against breast cancer (MCF-7), cervical cancer (HeLa), and Lung cancer (A549) cell lines. Hybrid molecules 5a, 5m, 5n, and 5o with IC₅₀ values of 0.359 mM, 0.051 mM, 0.079 mM, and 0.259 mM respectively exhibited admirable growth inhibitory properties against MCF-7 cancer cells which are even better than reference carboplatin drug having IC₅₀ (0.439 mM). Compound 5k with IC₅₀ value of 0.765 mM was found to be the most potent antiproliferative agent for the HeLa cancer cells. Moreover, hybrid molecule 5f with IC₅₀ value of 0.706 mM exhibited better inhibitory activity against A549 cancer cells in comparison to the reference carboplatin drug having IC₅₀ (0.805 mM). The mechanism of cellular toxicity was studied using the Annexin V-FITC/PI double staining method and cell cycle assay. Molecular docking studies for all the synthesized compounds have also been performed in the binding pocket of VEGFR2 sites (PDB code: 4ASD). Finally, the ADMET profile of the potent molecules was investigated to predict their drug-likeness behaviour.

Ionic liquids (ILs) are incorporated into traditional porous materials to create ILs-functionalized porous materials, which exhibit excellent absorption capacity and good catalytic activity for CO₂. As a result, they are extensively utilized in the chemical conversion of CO₂. This paper specifically focuses on the utilization of ILs-functionalized organic porous materials, ILs-functionalized inorganic porous materials, and ILs-functionalized organic-inorganic hybrid porous materials in the conversion of CO₂. The synergistic effects of combining ILs with porous materials in CO₂ conversion are thoroughly discussed. Furthermore, an in-depth analysis is provided regarding the potential prospects and future applications of utilizing ILs-functionalized porous materials within the broader realm of catalytic CO₂ conversion technologies.

Nanomaterials have revolutionized various scientific and industrial domains due to their exceptional properties and diverse applications. Yet, challenges persist in achieving their controlled synthesis, stability, and recyclability, especially in catalysis. Organoselenium compounds are emerging as promising agents for the stabilization of nanomaterials, with high prospects for catalytic applications. This article covers the recent strides made in harnessing the potential of organoselenium compounds to stabilize diverse nanomaterials with applications in catalysis. Specifically, it delves into their effectiveness in Suzuki-Miyaura cross-coupling, C−O coupling, Sonogashira coupling, reduction of nitroarenes, synthesis of primary amides (in aqueous medium), and offers a comprehensive overview of this evolving field.

Visible-light-driven dual catalysis was employed to stereoselectively produce densely substituted cyclobutanes from Erlenmeyer-Plöchl azlactones. The single-step preparation of non-natural amino acid dimers containing the cyclobutane moiety was achieved through a synergy between iridium photocatalysis and catalytic nickel(II) triflate as a Lewis acid. The desired 1,2-(zeta)-Z,E-isomers were isolated in good yields and with high regio- and diastereoselectivity (in all cases, >19 : 1 d.r.). To the best of our knowledge, this is the first report of direct access to truxinic acid analogues using azlactones. Control experiments, EPR reaction monitoring, and DFT calculations suggest that the presence of a Lewis acid, combined with the use of powerful blue LEDs, plays a crucial role in the reactivity of this reaction.

A metal-free one-pot synthesis route has been documented for the production of 1,1-unsymmetrical di-aryl alkanes via reductive Friedel−Crafts alkylation of arenes with carbonyl compounds in 1,1,1,3,3,3,–hexafluoroisopropanol (HFIP) solvent. This approach exhibits a wide substrate scope accommodating diverse functionalities. The transformation of carbonyl compounds into alkylated products is facilitated by dimethylchlorosilane (Me₂SiClH) reduction, succeeded via nucleophilic attack of arenes. The established protocol demonstrates a promising strategy for converting indoline-2,3-dione into α-aryl oxindoles with high yields. The reaction involves reduction with Me₂SiClH, followed by the attack of arenes in the presence of a TfOH catalyst. The devised protocol offers scalability and remarkable tolerance towards various functional groups. Control experiments provide insights into the reaction mechanism, highlighting the crucial roles of HFIP and Me₂SiClH. Furthermore, the method is adaptable for late-stage functionalization of numerous natural products and pharmaceuticals such as Sesamol, Thymol, Paracetamol, Menthol, and Nerol. Significantly, the technique has proven effective in efficiently synthesising the anticoagulant drug Phenprocoumon and the rodent control agent Coumatetralyl.

A new approach of dual visible light-induced gold(III)-catalyzed alkynylation and its application in selective modification of alkyne-linked peptides has been developed. The bis-cyclometalated gold(III) complex exhibited dual roles of (1) in situ generation of quinolizinium-based photosensitizer (λ_em=500 – 594 nm) and (2) alkynylation of iminium ions. Under optimized conditions, alkynylated products were afforded in good yields up to 73 %. The application of this strategy in selective modification of alkyne-linked peptides gave modified peptides in up to 67 % conversion. Our dual visible light/gold(III) catalysis exemplifies the potential of merging photocatalysis and transition metal catalysis to develop novel bioconjugation.

The cover design showcases a general method for the synthesis of sulfenamides from various benzoazole-2-thiones with amines using bismuth reagent. The brother′s azole-thiones and the sister′s amines being reacted with the bismuth reagent to produce the sulfenamide that blooms beautifully like fireworks. In the night sky, the S-N bond formation is depicted to resemble the Milky Way. The reactions of benzoazole-2-thiones with various primary or secondary amines in the presence of triphenylbismuth dichloride (Ph3BiCl2) at 60 °C in DMSO under aerobic conditions afforded the corresponding sulfenamides in moderate-to-excellent yields. This reaction is the first example of an efficient S–N bond formation reaction utilizing a lowtoxicity pentavalent organobismuth reagent under mild reaction conditions. The reaction will likely be applied to develop compounds with medicinal value or industrial utility. More information can be found in article number e202400138 by Yuki Murata, Shuji Yasuike, and co-workers.

Over the past three decades, triflate salts have emerged as crucial Lewis acid catalysts in organic synthesis, playing a significant role in cyclization, C−H bond functionalization, and various other reactions. Among these, rare-earth triflates have garnered attention due to their water compatibility, environmental friendliness, noncorrosive nature, and reusability. In particular, scandium(III) triflate [Sc(OTf)₃] stands out as a water-resistant Lewis acid with remarkable catalytic activity in aqueous environments. Unlike typical Lewis acids such as AlCl₃, BF₃, and SnCl₄, which are decomposed or deactivated by water, Sc(OTf)₃ remains stable and effective. Its exceptional Lewis acidity, resilience against hydrolysis, and recyclability make it a prominent green catalyst. The unique stability of Sc(OTf)₃ in water is attributed to the smaller size of scandium ions (Sc³⁺), enhancing its catalytic efficiency. Sc(OTf)₃ has a longstanding history in organic synthesis, facilitating a wide range of reactions including aldol, Michael, allylation, Friedel-Crafts acylations, Diels-Alder, Mannich, cycloadditions (including cyclopropanation), and cascade reactions. The increasing utilization of Sc(OTf)₃ over the past decade underscores the necessity for updated insights. This review provides a concise overview of the versatility of Sc(OTf)₃ as a catalyst, focusing on developments from 2017 to 2024.