32347-03-8Relevant academic research and scientific papers
Tris-NHC-propagated self-supported polymer-based Pd catalysts for heterogeneous C-H functionalization
Choudhury, Joyanta,Dutta, Tapas Kumar,Mandal, Tanmoy,Mohanty, Sunit
supporting information, p. 10182 - 10185 (2021/10/12)
Three-dimensionally propagated imidazolium-containing mesoporous coordination polymer and organic polymer-based platforms were successfully exploited to develop single-site heterogenized Pd-NHC catalysts for oxidative arene/heteroarene C-H functionalization reactions. The catalysts were efficient in directed arene halogenation, and nondirected arene and heteroarene arylation reactions. High catalytic activity, excellent heterogeneity and recyclability were offered by these systems making them promising candidates in the area of heterogeneous C-H functionalization, where efficient catalysts are still scarce.
A Short Approach to N -Aryl-1,2,3,4-tetrahydroisoquinolines from N -(2-Bromobenzyl)anilines via a Reductive Amination/Palladium-Catalyzed Ethoxyvinylation/Reductive N -Alkylation Sequence
Glas, Carina,Wirawan, Ricky,Bracher, Franz
, p. 1943 - 1954 (2021/01/18)
N -Aryl-1,2,3,4-tetrahydroisoquinolines are obtained via a convenient and short protocol with a broad range of substituents on both aromatic rings and high functional group tolerance. Starting from readily available ortho -brominated aromatic aldehydes and primary aromatic amines, condensation of these building blocks under reductive conditions gives N -aryl 2-bromobenzylamines. The C-3/C-4-unit of the tetrahydroisoquinoline is introduced using commercially available 2-ethoxyvinyl pinacolboronate under Suzuki conditions. Finally, the obtained crude ortho -ethoxyvinyl benzylamines are cyclized via an intramolecular reductive amination using the combination of triethylsilane/TFA to give the desired N -aryl-1,2,3,4-tetrahydroisoquinolines.
Manganese-Catalyzed Electrochemical Tandem Azidation-Coarctate Reaction: Easy Access to 2-Azo-benzonitriles
Maiti, Debabrata,Mahanty, Kingshuk,De Sarkar, Suman
supporting information, p. 1742 - 1747 (2021/04/05)
A one-pot cascade transformation consisting of an electrochemically driven azidation of 2H-indazole followed by coarctate fragmentation is developed to synthesize the 2-azo-benzonitrile motif. This manganese-catalyzed transformation is external-chemical-oxidant-free and operates at ambient temperature under air. This methodology exhibits good functional group tolerance, affording a broad range of substrate scopes of up to 89% isolated yield. Diverse derivatization of the 2-azo-benzonitrile product resulted in other valuable scaffolds.
Oxidative cross-dehydrogenative coupling (CDC)viaC(sp2)-H bond functionalization:tert-butyl peroxybenzoate (TBPB)-promoted regioselective direct C-3 acylation/benzoylation of 2H-indazoles with aldehydes/benzyl alcohols/styrenes
Sharma, Richa,Yadav, Lalit,Yadav, Ravi Kant,Chaudhary, Sandeep
, p. 14178 - 14192 (2021/04/22)
An efficient, cost-effective, transition-metal-free, oxidative C(sp2)-H/C(sp2)-H cross-dehydrogenative couplingviaa C(sp2)-H bond functionalization protocol for the regioselective direct C-3 acylation/benzoylation of subst
Inverse Hydroboration of Imines with NHC-Boranes Is Promoted by Diphenyl Disulfide and Visible Light
Kawamoto, Takuji,Morioka, Tsubasa,Noguchi, Kohki,Curran, Dennis P.,Kamimura, Akio
supporting information, p. 1825 - 1828 (2021/03/08)
We describe a simple and efficient procedure for nucleophilic borylation of imines in the absence of a photoredox catalyst. Visible light irradiation of an acetonitrile solution of an imine, an NHC-borane, and diphenyl disulfide (10 mol %) provides various stable α-amino NHC-boranes in good yields. The reaction proceeds via addition of a nucleophilic boryl radical to an imine, followed by hydrogen abstraction from thiophenol, which is generated from NHC-borane and diphenyl disulfide.
Hypercrosslinked Polymer Platform-Anchored Single-Site Heterogeneous Pd-NHC Catalysts for Diverse C-H Functionalization
Mandal, Tanmoy,Mondal, Moumita,Choudhury, Joyanta
supporting information, p. 2443 - 2449 (2021/08/03)
We demonstrate a new class of hypercrosslinked polymer (HCP) platform-Anchored single-site heterogenized Pd-NHC catalysts for multipurpose C-H functionalization reactions. This new class is represented by a set of three catalysts, viz., HCP-B-MeNHC-Pd, HCP-B-BnNHC-Pd, and HCP-TPM-MeNHC-Pd, having a variation on the structural feature of the anchoring polymeric platform. All three catalysts were fully characterized via diverse solid-state characterization and analytical techniques such as X-ray photoelectron spectroscopy, 13C cross-polarization magic-Angle-spinning nuclear magnetic resonance, field-emission scanning electron microscopy, energy-dispersive X-ray analysis, thermogravimetric analysis, and inductively coupled plasma-optical emission spectrometry. Three types of regularly practiced and very useful C-H functionalization reactions, viz., C-H halogenation, acetoxylation, and arylation, are tested with the new catalysts and found to be highly compatible and successful. With the HCP-TPM-MeNHC-Pd catalyst, up to 85, 75, and 70% yields of the functionalized products were achieved for the halogenation, acetoxylation, and arylation reactions, respectively. Demanding attributes such as enhanced activity, heterogeneity, and recyclability are offered by this new system, making it a promising candidate in the field of heterogeneous C-H functionalization, where only a few efficient catalysts are available.
Method for synthesizing aluminum phosphate molecular sieve catalytic imine
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Paragraph 0041-0043, (2020/06/02)
The invention discloses a method for catalyzing synthesis of an imine by using an aluminum phosphate molecular sieve, and belongs to the technical field of catalytic synthesis of imines. Under the action of an HP-MeAlPO-5 molecular sieve, air or oxygen is used as an oxidant, and an amine and an alcohol which contain different substituents are directly subjected to oxidative coupling to synthesizethe imine under mild conditions. According to the method provided by the invention, the reaction conditions of the adopted catalytic system are mild, and the TOF is high; a reaction can efficiently catalyze the synthesis of the imine at room temperature under air; and the method can adopt transition metals, which are cheap and easy to obtain, such as iron, cobalt and nickel as a molecular sieve dopant, and the availability of the molecular sieve is improved.
Cross dehydrogenative coupling strategy for allylation of benzylanilines promoted by DDQ
Xiong, Ruimei,Hussain, Muhammad Ijaz,Liu, Qing,Xia, Wen,Xiong, Yan
supporting information, (2019/12/11)
A cross dehydrogenative coupling strategy for allylation of benzylanilines promoted by DDQ is reported, which uses nonmetallic quinone DDQ as an oxidant in the allylation of N-benzylanilines under mild conditions. C–C bond with high selectivity and activity was constructed in this reaction and homoallylic amines were obtained with yields of up to 99%.
Retraction: Harnessing Thiol as a Benzyl Reagent for Photocatalytic Reductive Benzylation of Imines (Organic Letters DOI: 10.1021/2Facs.orglett.0c00065)
Zhang, Jinghui,Zhang, Muliang
supporting information, p. 2112 - 2112 (2020/02/15)
The authors retract this article after finding in subsequent studies that the quality of the purchased catalysts has a notable impact on the reproducibility of the results. Accordingly, the authors note that additional work is necessary to understand the
Bu4NI-catalyzed, oxidative C(sp2)-C(sp3)cross dehydrogenative coupling for the regioselective direct C-3 benzylation of 2: H -indazoles
Chaudhary, Sandeep,Yadav, Lalit
, p. 5927 - 5936 (2020/08/21)
A Bu4NI-catalyzed, DTBP-promoted, regioselective C(sp2)-C(sp3) cross dehydrogenative coupling (CDC) protocol for the direct C-3 benzylation of 2H-indazoles is reported. The metal-free protocol is operationally simple and proceeds mechanistically via the g
