60456-78-2Relevant academic research and scientific papers
Direct (Hetero)arylation of Heteroarenes Catalyzed by Unsymmetrical Pd-PEPPSI-NHC Complexes under Mild Conditions
Song, A-Xiang,Zeng, Xiao-Xiao,Ma, Bei-Bei,Xu, Chang,Liu, Feng-Shou
, p. 3524 - 3534 (2020/10/09)
With the aim of developing a facile and efficient method to access structurally intriguing and valuable functionalized (hetero)aryls, two unsymmetrical Pd-PEPPSI-type NHC complexes (PEPPSI, pyridine-enhanced precatalyst preparation, stabilization, and initiation; NHC, N-heterocyclic carbene) were designed and synthesized to catalyze the direct arylation of heteroarenes with (hetero)aryl bromides. The results demonstrated that the utilization of this "unsymmetrical"strategy led to much higher efficiency in comparison to the commonly used C2-symmetric Pd-PEPPSI-type NHC complexes. Furthermore, a broad range of heteroaromatics and (hetero)aryl bromide partners with a wide variety of functional groups were all amenable to the developed protocol even at as low as 0.05 mol % catalyst loading and under aerobic conditions. More importantly, along with our study, we also found that the present protocol could provide expedient access to the gram-scale synthesis of the muscle relaxant drug dantrolene and conjugated mesopolymers.
C–H Arylation of N-Heteroarenes under Metal-Free Conditions and its Application towards the Synthesis of Pentabromo- and Pentachloropseudilins
Kumar, Mukesh,Sharma, Shweta,Sil, Parijat,Kushwaha, Manoj,Mayor, Satyajit,Vishwakarma, Ram A.,Singh, Parvinder Pal
supporting information, p. 3591 - 3598 (2019/06/20)
Herein, we are reporting metal-free conditions for radical initiation and direct C–H arylation of N-heteroarenes. Starting from aniline, the corresponding arenediazonium salt generated in situ is reduced to an aryl radical in the presence of chloropromazine hydrochloride, a new reagent for this application. The optimized procedures are mild, operationally simple, and are working successfully with more diverse substrates in comparison to reported methods. The optimized method is also employed for the synthesis of marine natural products Pentabromo- and Pentachloropseudilins (PBP/PCP). In the present study, we also validated the potential of the Pentachloropseudilin (PCP), thus synthesized, for inhibition of Myosin1 function in mammalian cells and confirmed that PCP phenocopies Myosin1c depletion in cells.
Merging visible-light photoredox and micellar catalysis: Arylation reactions with anilines nitrosated in situ
Bu, Mei-Jie,Lu, Guo-Ping,Jiang, Jianzhong,Cai, Chun
, p. 3728 - 3732 (2018/08/12)
An aqueous photocatalytic system was designed by merging visible-light photoredox catalysis with micellar catalysis. Eosin B, an organic dye, was utilized as the photocatalyst, and Triton X-100 was employed as the surfactant; both are inexpensive and commercially available. This clean and energy-saving catalytic system enables photocatalytic reactions of the diazonium ion generated in situ to proceed smoothly in water without any co-solvents or additives at room temperature.
Method for synthesizing substituted furan
-
Paragraph 0010, (2017/12/09)
Provided is a method for synthesizing substituted furan. Iodohydrocarbon and terminal propargyl alcohol produce Sonogashira coupling reaction to generate an intermediate product 3-alkyne-1-alcohol, then isomeric cyclization occurs under the effect of Dess
Visible-light photocatalyzed synthesis of 2-aryl N-methylpyrroles, furans and thiophenes utilizing arylsulfonyl chlorides as a coupling partner
Natarajan, Palani,Bala, Anu,Mehta,Bhasin
, p. 2521 - 2526 (2016/04/26)
Visible-light (Blue LED lamp: hν=425±15 nm) photocatalyzed cross-coupling reactions of arylsulfonyl chloride with N-methylpyrrole, furan, thiophene and their derivatives have been achieved in moderate to good yields at room temperature. A plausible mechan
Polyaniline-Induced C-H Arylation of Arenes with Arenediazonium Salts
Amaya, Toru,Hata, Dai,Moriuchi, Toshiyuki,Hirao, Toshikazu
, p. 16427 - 16433 (2015/11/10)
A reduced form of polyaniline has been shown to induce direct arylation of an arenediazonium salt with an arene (Gomberg-Bachmann reaction) to give the cross-coupling product in moderate to good yields under mild conditions. Various arenediazonium salts and arenes, including heteroarenes such as furans, thiophenes, and pyrroles, are employed for the reaction. The most favorable combination of substrates is an electron-poor arenediazonium salt with an electron-rich heteroarene. Investigation of the mechanism by reactions with radical scavengers and experiments on kinetic isotope effects indicated the occurrence of a radical chain reaction initiated by one-electron reduction of an arenediazonium salt by the polyaniline. Only 1 mol % (based on aniline tetramer) of the polyaniline is required for the cross-coupling reaction to occur. This reaction proceeds under metal-free conditions and with no need for photonic activation.
Eco-friendly solvents for palladium-catalyzed desulfitative C-H bond arylation of heteroarenes
Hfaiedh, Anoir,Yuan, Kedong,Ben Ammar, Hamed,Ben Hassine, Bechir,Soulé, Jean-Fran?ois,Doucet, Henri
, p. 1794 - 1804 (2015/06/02)
Herein, we report the Pd-catalyzed regioselective direct arylation of heteroarenes in which benzenesulfonyl chlorides are used as coupling partners through a desulfitative cross-coupling that can be performed in diethyl carbonate (DEC) or cyclopentyl methyl ether (CPME) as green and renewable solvents or even in neat conditions instead of dioxane or dimethylacetamide (DMA). Under these solvent conditions, the reaction proceeds with a wide range of heteroarenes. C2- or C5-arylated products were obtained with furan and pyrrole derivatives. Benzofuran was also arylated regioselectively at the C2-position, whereas the reaction proceeds selectively at the C3- or C4-positions if thiophenes and benzothiophenes are used. Moreover, in some cases, especially with 1-methylindole, solvent-free conditions afforded better regioselectivities and/or yields than the reaction performed in the presence of solvents.
AgONO-Assisted Direct C-H Arylation of Heteroarenes with Anilines
Gowrisankar, Saravanan,Seayad, Jayasree
supporting information, p. 12754 - 12758 (2015/03/30)
A novel copper-catalyzed C-H arylation of heteroarenes with anilines by an in situ diazonium reaction is established by using silver nitrite (AgONO) as an unconventional nitrosating reagent under acid-free conditions. It provides a complementary approach for the C-H arylation of electron-rich heteroarenes with aromatic amines affording a variety of heterobiaryls in moderate to good yields.
Ionic liquid as catalyst and reaction medium: A Simple and Efficient Procedure for Paal-Knorr furan synthesis
Wang, Gangqiang,Guan, Zhi,Tang, Rongchang,He, Yanhong
experimental part, p. 370 - 377 (2010/04/04)
The ionic liquid 1-butyl-3-methyl-imidazolium hydrogen sulfate, [bmim]HSO4, efficiently catalyzes Paal-Knorr furan synthesis without any organic solvent. A wide range of aliphatic and aromatic 1,4-diketones easily undergo condensations to form furan derivatives, providing a general and convenient procedure. The Paal-Knorr reaction of ester-substituted 1,4-diketones is first reported. The ionic liquid can be recovered and reused for subsequent runs without any appreciable loss of efficiency.
2,5-Disubstituted furans from 1,4-alkynediols
Pridmore, Simon J.,Slatford, Paul A.,Williams, Jonathan M.J.
, p. 5111 - 5114 (2008/02/09)
1,4-Alkynediols serve as readily available starting materials for isomerisation to 1,4-diketones, which can be converted in situ into the corresponding furans by acid-catalysed dehydration. A range of 2,5-disubstituted furans was prepared using the ruthenium-based catalyst Ru(PPh3)3(CO)H2 with Xantphos at 1 mol % loading.
