43019-96-1Relevant academic research and scientific papers
Nickel-mediated C(sp2)-H amidation in synthesis of secondary sulfonamides via sulfonyl azides as amino source
Xu, Peng,Ding, Peng-Fei,Zhang, Mei-Qi,Xia, Yu-Shi,Xie, Ting
supporting information, (2021/02/16)
In this paper, Ni(II)- Catalyzed ortho-amidation of C(sp2)-H bond with sulfonyl azides directed by (quinolin-8-yl) amine (AQ-amine) is described. The method provides a straightforward method for the synthesis of sulfonamides from available sulfonyl azides via the transition-metal-catalyzed C(sp2)-N bond forming reaction. The amidation reactions exhibit high functional group compatibility, which might proceed a Ni(III)/Ni(I) catalytic cycle. We also applied sulfonamide compound in OLEDs, which exhibits the certain application potential in OLEDs field.
Copper-mediated C–H thiolation of (hetero)arenes using weakly coordinating directing group
Wu, Peng,Cheng, Tai-Jin,Lin, Hai-Xia,Xu, Hui,Dai, Hui-Xiong
supporting information, (2020/06/17)
We have developed a copper-mediated C–H thiolation of (hetero)arenes by using monodentate amide as weakly coordinating directing group. This protocol features excellent functional group tolerance and shows satisfactory compatibility with various heterocycles, such as indole, pyrrole, imidazole, pyridine, thiophene and quinoline. The robust nature of this protocol renders that it has potential value in the synthetic application.
Co(III)-Catalyzed [4+1] Annulation of Amides with Allenes via C?H Activation
Boobalan, Ramadoss,Santhoshkumar, Rajagopal,Cheng, Chien-Hong
supporting information, p. 1140 - 1145 (2019/01/30)
A Co(III)-catalyzed [4+1] annulation of amides with allenes to synthesize isoindolone and 1,5-dihydro-pyrrol-2-one derivatives is reported. A wide range of aromatic and vinylic amides react with allenes to give the corresponding annulation products in good to excellent yields. The mechanistic studies strongly support that the catalytic reaction proceeds through an amide-directed C?H activation, followed by carbocobaltation of allene, β-hydride elimination, and an intramolecular 1,2-hydroamination. (Figure presented.).
Cp?CoIII-Catalyzed syn-Selective C-H Hydroarylation of Alkynes Using Benzamides: An Approach Toward Highly Conjugated Organic Frameworks
Bera, Sourav Sekhar,Debbarma, Suvankar,Ghosh, Avick Kumar,Chand, Santanu,Maji, Modhu Sudan
, p. 420 - 430 (2017/04/26)
Hydroarylation of internal alkynes by cost-effective CoIII-catalysis, directed by N-tert-butyl amides, is achieved to avail mono- or dihydroarylated amide products selectively in an atom and step economic way. Several important functional groups were tolerated under the reaction conditions, and syn-hydroarylation products were exclusively isolated. Notably, a 4-fold C-H hydroarylation provided a highly conjugated organic framework in one step. Kinetic study with extensive deuterium labeling experiments were performed to support the proposed mechanism.
General C-H Arylation Strategy for the Synthesis of Tunable Visible Light-Emitting Benzo[a]imidazo[2,1,5-c,d]indolizine Fluorophores
Lévesque, éric,Bechara, William S.,Constantineau-Forget, Léa,Pelletier, Guillaume,Rachel, Natalie M.,Pelletier, Joelle N.,Charette, André B.
, p. 5046 - 5067 (2017/05/24)
Herein we report the discovery of the benzo[a]imidazo[2,1,5-c,d]indolizine motif displaying tunable emission covering most of the visible spectrum. The polycyclic core is obtained from readily available amides via a chemoselective process involving Tf2O-mediated amide cyclodehydration, followed by intramolecular C-H arylation. Additionally, these fluorescent heterocycles are easily functionalized using electrophilic reagents, enabling divergent access to varied substitution. The effects of said substitution on the compounds' photophysical properties were rationalized by density functional theory calculations. For some compounds, emission wavelengths are directly correlated to the substituent's Hammett constants. Easily introduced nonconjugated reactive functional groups allow the labeling of biomolecules without modification of emissive properties. This work provides a straightforward platform for the synthesis of new moderately bright fluorescent dyes remarkable for their chemical stability, predictability, and unusually high excitation-emission differential.
Synthesis of isoquinolones: Via Rh-catalyzed C-H activation of substituted benzamides using air as the sole oxidant in water
Upadhyay, Nitinkumar Satyadev,Thorat, Vijaykumar H.,Sato, Ryota,Annamalai, Pratheepkumar,Chuang, Shih-Ching,Cheng, Chien-Hong
supporting information, p. 3219 - 3224 (2017/07/28)
Most of the metal-catalyzed C-H activation/annulation reactions were carried out in organic solvents using expensive oxidants such as Cu(ii) and Ag(i) salts. Here, we reported a new approach for a highly regioselective synthesis of isoquinolones from N-alkyl benzamides and alkynes using an Rh(iii) catalyst and inexpensive oxygen as the sole oxidant in an aqueous medium. In the reaction, water gave the highest product yield among the solvents used. In addition, at the end of the reaction, the isoquinolone product directly precipitated out from the aqueous solution. The methodology can be applied to a gram scale synthesis. This Rh(iii)-catalyzed reaction shows interesting meta selectivity with the meta substituted benzamide and shows various regioselectivities with different substituted alkynes. Moreover, the methodology can be applied to the preparation of biologically active compounds having the isoquinolone core.
Ruthenium-Catalyzed C-H Alkynylation of Aromatic Amides with Hypervalent Iodine-Alkyne Reagents
Boobalan, Ramadoss,Gandeepan, Parthasarathy,Cheng, Chien-Hong
supporting information, p. 3314 - 3317 (2016/07/23)
An efficient C-H activation method for the ortho alkynylation of aromatic N-methoxyamides with hypervalent iodine-alkyne reagent using a ruthenium catalyst is described. The reaction proceeds under mild reaction conditions with broad substrate scope. A possible catalytic cycle involving a ruthenium carboxylate assisted C-H bond cleavage is proposed from the preliminary mechanistic evidence.
Copper/silver-mediated direct ortho-ethynylation of unactivated (hetero)aryl C-H bonds with terminal alkyne
Liu, Yue-Jin,Liu, Yan-Hua,Yin, Xue-Song,Gu, Wen-Jia,Shi, Bing-Feng
supporting information, p. 205 - 209 (2015/02/19)
A copper/silver-mediated oxidative ortho-ethynylation of unactivated aryl C-H bonds with terminal alkyne has been developed.The reaction uses the removable PIP directing group and features broad substrate scope, high functional-group tolerance, and compatibility with a wide range of heterocycles, providing an efficient synthesis of aryl alkynes. This procedure highlights the potential of copper catalysts to promote unique, synthetically enabling C-H functionalization reactions that lie outside of the current scope of precious metal catalysis.
Rh-catalyzed oxidizing group-directed ortho C-H vinylation of arenes by vinylstannanes
Prakash, Sekar,Muralirajan, Krishnamoorthy,Cheng, Chien-Hong
supporting information, p. 13362 - 13364 (2015/08/24)
An efficient method for the synthesis of functionalized vinyl arenes from the reaction of N-methoxybenzamides or N-phenoxyacetamides with vinylstannanes via rhodium(III)-catalyzed C-H activation is described. The application of the methodology for the synthesis of a natural product thalactamine and a 7-membered ring oxepine are also demonstrated.
Copper-mediated hydroxylation of arenes and heteroarenes directed by a removable bidentate auxiliary
Li, Xin,Liu, Yan-Hua,Gu, Wen-Jia,Li, Bo,Chen, Fa-Jie,Shi, Bing-Feng
supporting information, p. 3904 - 3907 (2014/08/18)
A copper-mediated C-H hydroxylation of arenes and heteroarenes using our newly developed PIP directing group has been developed. This procedure is scalable and compatible with a wide range of functional groups and heteroarenes, providing an operationally simple protocol for the synthesis of o-hydroxybenzamides. The hydroxylation of nicotinamides gave 4-oxo-1,4-dihydropyridine-3-carboxamides selectively. Preliminary mechanistic studies implicate that a basic ligand-enabled, irreversible, rate-determining CMD step is most likely involved in this process.
