76472-81-6Relevant articles and documents
Nickel-Catalyzed Electrochemical C(sp3)?C(sp2) Cross-Coupling Reactions of Benzyl Trifluoroborate and Organic Halides**
Luo, Jian,Hu, Bo,Wu, Wenda,Hu, Maowei,Liu, T. Leo
, p. 6107 - 6116 (2021/02/01)
Reported here is the redox neutral electrochemical C(sp2)?C(sp3) cross-coupling reaction of bench-stable aryl halides or β-bromostyrene (electrophiles) and benzylic trifluoroborates (nucleophiles) using nonprecious, bench-stable NiCl2?glyme/polypyridine catalysts in an undivided cell configuration under ambient conditions. The broad reaction scope and good yields of the Ni-catalyzed electrochemical coupling reactions were confirmed by 50 examples of aryl/β-styrenyl chloride/bromide and benzylic trifluoroborates. Potential applications were demonstrated by electrosynthesis and late-stage functionalization of pharmaceuticals and natural amino acid modification, and three reactions were run on gram-scale in a flow-cell electrolyzer. The electrochemical C?C cross-coupling reactions proceed through an unconventional radical transmetalation mechanism. This method is highly productive and expected to find wide-spread applications in organic synthesis.
Metal-organic layers as multifunctional two-dimensional nanomaterials for enhanced photoredox catalysis
Lan, Guangxu,Quan, Yangjian,Wang, Maolin,Nash, Geoffrey T.,You, Eric,Song, Yang,Veroneau, Samuel S.,Jiang, Xiaomin,Lin, Wenbin
supporting information, p. 15767 - 15772 (2019/10/11)
Metal-organic layers (MOLs) have recently emerged as a novel class of molecular two-dimensional (2D) materials with significant potential for catalytic applications. Herein we report the design of a new multifunctional MOL, Hf12-Ir-Ni, by laterally linking Hf12 secondary building units (SBUs) with photosensitizing Ir(DBB)[dF(CF3)ppy]2+ [DBB-Ir-F, DBB = 4,4′-di(4-benzoato)-2,2′-bipyridine; dF(CF3)ppy = 2-(2,4-difluorophenyl)-5-(trifluoromethyl)pyridine] bridging ligands and vertically terminating the SBUs with catalytic Ni(MBA)Cl2 [MBA = 2-(4′-methyl-[2,2′-bipyridin]-4-yl)acetate] capping agents. Hf12-Ir-Ni was synthesized in a bottom-up approach and characterized by TEM, AFM, PXRD, TGA, NMR, ICP-MS, UV-vis, and luminescence spectroscopy. The proximity between photosensitizing Ir centers and catalytic Ni centers (～0.85 nm) in Hf12-Ir-Ni facilitates single electron transfer, leading to a 15-fold increase in photoredox reactivity. Hf12-Ir-Ni was highly effective in catalytic C-S, C-O, and C-C cross-coupling reactions with broad substrate scopes and turnover numbers of ～4500, ～1900, and ～450, respectively.
Cross-Coupling of Phenol Derivatives with Umpolung Aldehydes Catalyzed by Nickel
Lv, Leiyang,Zhu, Dianhu,Tang, Jianting,Qiu, Zihang,Li, Chen-Chen,Gao, Jian,Li, Chao-Jun
, p. 4622 - 4627 (2018/05/22)
A nickel-catalyzed cross-coupling to construct the C(sp2)-C(sp3) bond was developed from two sustainable biomass-based feedstocks: phenol derivatives with umpolung aldehydes. This strategy features the in situ generation of moisture/air-stable hydrazones from naturally abundant aldehydes, which act as alkyl nucleophiles under catalysis to couple with readily available phenol derivatives. The avoidance of using both halides as the electrophiles and organometallic or organoboron reagents (also derived from halides) as the nucleophiles makes this method more sustainable. Water tolerance, great functional group (ketone, ester, free amine, amide, etc.) compatibility, and late-stage elaboration of complex biological molecules exemplified its practicability and unique chemoselectivity over organometallic reagents.
Single-electron transmetalation in organoboron cross-coupling by photoredox/nickel dual catalysis
Tellis, John C.,Primer, David N.,Molander, Gary A.
, p. 433 - 436 (2014/08/05)
The routine application of Csp3-hybridized nucleophiles in cross-coupling reactions remains an unsolved challenge in organic chemistry. The sluggish transmetalation rates observed for the preferred organoboron reagents in such transformations are a consequence of the two-electron mechanism underlying the standard catalytic approach. We describe a mechanistically distinct single-electron transfer-based strategy for the activation of organoboron reagents toward transmetalation that exhibits complementary reactivity patterns. Application of an iridium photoredox catalyst in tandem with a nickel catalyst effects the cross-coupling of potassium alkoxyalkyl- and benzyltrifluoroborates with an array of aryl bromides under exceptionally mild conditions (visible light, ambient temperature, no strong base). The transformation has been extended to the asymmetric and stereoconvergent cross-coupling of a secondary benzyltrifluoroborate.
Solvent free acid catalysed direct N-alkylation of amines with alcohols using Al grafted MCM-41
Tayade, Kamlesh N.,Mishra, Manish,Munusamy,Somani, Rajesh S.
, p. 91 - 96 (2014/06/24)
The catalytic activity of Al grafted MCM-41 (Al-MS) was explored for solvent free acid catalysed direct N-alkylation of amines using alcohols as green alkylating agent to establish a clean method for synthesis of N-alkylated amines. The study revealed that acidity of Al-MS catalyst, reaction conditions and substrate's (amines and alcohols) nature are important factors influencing the N-alkylation reaction. The Al grafted MCM-41 with Si/Al molar ratio of 5 showed excellent activity for N-alkylation of amines with alcohols. The reusability of spent catalyst regenerated by simple washing with acetone was demonstrated for subsequent four reaction cycles.
Acid-Catalyzed Reactions of N-Arylhydroxylamines and Related Compounds with Benzene. Iminium-Benzenium Ions
Shudo, Koichi,Ohta, Toshiharu,Okamoto, Toshihiko
, p. 645 - 653 (2007/10/02)
N-Arylhydroxylamines react with benzene in the presence of trifluoroacetic acid (TFA) at room temperature to give diphenylamines.When TFA was replaced by a strong acid, trifluoromethanesulfonic acid (TFSA), the major products were aminobiphenyls.The nature of the reaction was explored by reactions of 4-substituted phenylhydroxylamines and dialkylaniline N-oxides with benzene.Thus, it was demonstrated that the reactive intermediates are onium-benzenium dications which are trapped by benzene to give aminobiphenyls by a mechanism similar to the Friedel-Krafts alkylation.Further evidence for the proposed reaction mechanism was the observation that nitrosobenzene and azoxybenzene reacted with benzene to give analogous products in the presence of the stronger acid.
