6460-92-0Relevant articles and documents
Copper catalysed Gomberg-Bachmann-Hey reactions of arenediazonium tetrafluoroborates and heteroarenediazonium o-benzenedisulfonimides. Synthetic and mechanistic aspects
Antenucci, Achille,Barbero, Margherita,Dughera, Stefano,Ghigo, Giovanni
, (2020/10/20)
Gomberg-Bachmann-Hey reactions were carried out in the presence of copper as a catalyst and gave rise to biaryls or heterobiaryls in good yields and in mild reaction conditions. A computational study of some key points of the reaction was performed. The results are coherent with the experimental data and confirm some aspects of the mechanism. The reaction free energies for the reduction in benzene by CuI of a set of 40 (hetero)arenediazonium tetrafluoroborates were calculated. Both the experiments and the calculations showed that in the coupling with substituted solvents (toluene, bromobenzene, nitrobenzene and anisole) the binding to the ortho position was always favoured.
Tetramethylammonium fluoride tetrahydrate-mediated transition metal-free coupling of aryl iodides with unactivated arenes in air
Nozawa-Kumada, Kanako,Nakamura, Kosuke,Kurosu, Satoshi,Iwakawa, Yuki,Denneval, Charline,Shigeno, Masanori,Kondo, Yoshinori
, p. 1042 - 1045 (2019/10/02)
Biaryls are important compounds with widespread applications in many fields. Tetramethylammonium fluoride tetrahydrate was found to promote the biaryl coupling of aryl iodides bearing electron-withdrawing substituents with unactivated arenes. The reaction takes place at temperatures between 100 and 150°C and can be applied to a wide range of aromatic and heteroaromatic rings, affording the products in moderate to high yields. The reaction does not require strong bases or expensive additives that are employed in the existing methods and can be conducted in air and moisture without any precautions.
Arenediazonium Tosylates (ADTs) as Efficient Reagents for Suzuki-Miyaura Cross-Coupling in Neat Water
Kutonova, Ksenia V.,Jung, Nicole,Trusova, Marina E.,Filimonov, Victor D.,Postnikov, Pavel S.,Br?se, Stefan
, p. 1680 - 1688 (2017/03/21)
A simple, convenient, and environment-friendly procedure for the preparation of substituted biaryls via Suzuki-Miyaura cross-coupling- was developed. The use of arenediazonium tosylates and corresponding boron compounds allows a conversion in neat water in the presence of commercially available Pd(OAc)2 under mild conditions with tolerance to a wide range of functional groups. A procedure particularly useful for the synthesis of di-ortho-substituted biaryls was developed.
An active catalytic system for Suzuki-Miyaura cross-coupling reactions using low levels of palladium loading
Yan, Meng-Qi,Yuan, Jia,Lan, Fang,Zeng, Si-Hao,Gao, Meng-Yue,Liu, Sheng-Hua,Chen, Jian,Yu, Guang-Ao
supporting information, p. 3924 - 3929 (2017/07/10)
An easily available Pd(OAc)2/(2-(anthracen-9-yl)-1H-inden-3-yl) dicyclohexylphosphine/toluene/iPrOH/water catalytic system was developed, which shows high catalytic activity in the Suzuki-Miyaura cross-coupling reactions of a diverse array of aryl and heteroaryl chlorides with Pd loadings down to 0.01 mol%.
A Highly Efficient Pd(PPh3)4-Catalyzed Suzuki Cross-Coupling Method for the Preparation of 2-Nitrobiphenyls from 1-Chloro-2-nitrobenzenes and Phenylboronic Acids
Elumalai, Vijayaragavan,Sandtorv, Alexander H.,Bj?rsvik, Hans-René
, p. 1344 - 1354 (2016/03/16)
A simple and efficient method for Suzuki cross-coupling of highly substituted and congested 1-chloro-2-nitrobenzene with phenylboronic acid was developed, investigated, and optimized. The reaction conditions comprises a mixture of MeOH and water (4:1) as the reaction medium, readily available and cheap Pd(PPh3)4 as catalyst, sodium carbonate as base, and microwave heating, which affords a fast reaction rate with good outcomes. The procedure was proven to have high functional group tolerance with phenylboronic acid and for 1-chloro-2-nitrobenzene and thus is a general method for the synthesis of 2-nitrobiphenyl. The target scaffold, 2-nitrobiphenyls, was produced in excellent yields with excellent selectivities in all cases. An efficient microwave-assisted and Pd(PPh3)4-catalyzed Suzuki cross-coupling method for the synthesis of 2-nitrobiphenyls from 1-chloro-2-nitrobenzenes and phenylboronic acids is disclosed. The method exhibits excellent selectivity and fast reaction rates, provides high to excellent yields, and tolerates both electron-withdrawing and -donating groups.
COMPOUNDS AND METHODS FOR TREATING CANCERS
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Paragraph 0124, (2014/10/04)
Provided are carbazole and carbazole-like compounds (e.g., pyridoindole and pyrrolodipyridine) compounds, that can be used to selectively kill cancer cells, specifically androgen-receptor expressing prostate cancer cells. Also provided is a method of treating AR-positive prostate cancer in a subject diagnosed with or suspected of having AR positive or negative cancer, comprising administering an effective amount of a carbazole and carbazole-like compound to said subject.
Magnesium and calcium complexes containing biphenyl-based tridentate iminophenolate ligands for ring-opening polymerization of rac -lactide
Yi, Wei,Ma, Haiyan
, p. 11821 - 11835 (2013/11/19)
A series of racemic 2-[(2′-methoxybiphenyl-2-ylimino)methyl]-4-R 2-6-R1-phenols (L1H-L8H) were reacted with {Mg[N(SiMe3)2]2}2 and Ca[N(SiMe3)2]2·2THF (THF = tetrahydrofuran), respectively, to provide nine heteroleptic magnesium complexes L1-8MgN(SiMe3)2 [R1 = iPr, R2 = H (1a); R1 = tBu, R 2 = Me (2a and 2a·THF); R1 = R2 = tBu (3a); R1 = R2 = CMe2Ph (4a); R1 = CPh3, R2 = tBu (5a); R 1 = 1-piperidinylmethyl, R2 = tBu (6a); R 1 = Cl, R2 = tBu (7a); R1 = Br, R2 = tBu (8a)], two homoleptic calcium complexes (L 2,5)2Ca (2b and 5b), and one heteroleptic calcium complex [(L4)CaN(SiMe3)2·THF] (4b), which have been fully characterized. In the solid state, magnesium complexes 2a and 6a are isostructural, and each possesses a monomeric structure, while magnesium complexes 7a and 8a are dimeric, where the two metal centers are bridged by two phenolate oxygen atoms of the ligands. The coordination geometry around the magnesium center in these complexes can be best described as a distorted tetrahedral geometry. Although bearing the same iminophenoloate ligand, the molecular structures of complexes 2a and 2a·THF are different from each other. In complex 2a·THF, the coordination of one molecule of THF to the magnesium atom leads to dissociation of the methoxy group of the ligand from the metal center. The homoleptic calcium complex 2b has a six-coordinate metal core ligated by all six donor atoms of two iminophenolate ligands. The heteroleptic magnesium complexes 1a-8a and calcium complex 4b proved to be efficient initiators for the ring-opening polymerization of rac-lactide at ambient temperature in THF or at 70 C in toluene, and the polymerizations were better controlled in the presence of 2-propanol. The introduction of a bulky ortho substituent on the phenoxy unit of the ligand resulted in an increase of the catalytic activity of the corresponding metal complex. Microstructure analysis of the resultant poly(rac-lactide) samples via homonuclear-decoupled 1H NMR spectroscopy revealed Pr values ranging from 0.60 to 0.81, which closely depended on the employed catalyst and polymerization conditions.
Solvent-free synthesis of δ-carbolines/carbazoles from 3-nitro-2-phenylpyridines/2-nitrobiphenyl derivatives using DPPE as a reducing agent
Peng, Haixia,Chen, Xuxing,Chen, Yanhong,He, Qian,Xie, Yuyuan,Yang, Chunhao
experimental part, p. 5725 - 5731 (2011/08/09)
A green and efficient preparation of functionalized δ-carbolines/ carbazoles via reductive ring closure by 1,2-bis(dipenylphosphino)ethane under solvent-free conditions is described. The starting materials 3-nitro-2-phenylpyridines/2-nitrobiphenyl derivatives are readily prepared through Suzuki-Miyaura cross-coupling reaction from commercially available compounds. And the polar by-product ethane-1,2-diylbis(diphenylphosphine oxide) is easily removed from the relatively polar reaction mixture. Various substituted δ-carbolines/carbazoles are obtained in acceptable yields. It is particularly worth mentioning that substrates with electron-withdrawing groups (EWG) also give the desired products in good yield.
Palladium on activated carbon - A recyclable catalyst for Suzuki-Miyaura cross-coupling of aryl chlorides in water
Lysen, Morten,Koehler, Klaus
, p. 692 - 698 (2007/10/03)
Aryl chlorides are efficiently coupled with aryl boronic acids using ligandless Pd/C in water. The catalyst is easily recovered via filtration and reused up to four times with an overall yield of 73%. In addition the catalytic activity and selectivity of a variety of homogeneous and heterogeneous palladium sources have been compared. Georg Thieme Verlag Stuttgart.
Synthesis of 2-nitro- and 2,2′-dinitrobiphenyls by means of the suzuki cross-coupling reaction
Gonzalez, Raquel Rodriguez,Liguori, Lucia,Carrillo, Alberto Martinez,Bjorsvik, Hans-Rene
, p. 9591 - 9594 (2007/10/03)
Mechanistic investigations and protocols for the synthesis of 2-nitrobiphenyls and 2,2′-dinitrobiphenyls are disclosed. It is revealed that obstacles appear during the transmetalation step when the phenylboronic acid is substituted with a nitro group in the 2-position, whereas when substituted in the 3- or 4-positions, the reaction follows similar patterns as found in the electrophilic substitution of nitrobenzenes, an observation that may be attributed to the elimination step of the catalytic cycle.
