103-32-2Relevant academic research and scientific papers
Zinc-Catalyzed N-Alkylation of Aromatic Amines with Alcohols: A Ligand-Free Approach
Sankar, Velayudham,Kathiresan, Murugavel,Sivakumar, Bitragunta,Mannathan, Subramaniyan
, p. 4409 - 4414 (2020)
An efficient zinc-catalyzed N-alkylation reaction of aromatic amines was achieved using aliphatic, aromatic, and heteroaromatic alcohols as the alkylating reagent. A variety of aniline derivatives, including heteroaromatic amines, underwent the N-alkylation reaction and furnished the corresponding monoalkylated products in good to excellent yields. The application of the reaction is also further demonstrated by the synthesis of a 2-phenylquinoline derivative from acetophenone and 2-aminobenzyl alcohol. Deuterium labeling experiments show that the reaction proceeds via a borrowing hydrogen process. (Figure presented.).
Iron-Carbonyl-Catalyzed Redox-Neutral [4+2] Annulation of N-H Imines and Internal Alkynes by C-H Bond Activation
Jia, Teng,Zhao, Chongyang,He, Ruoyu,Chen, Hui,Wang, Congyang
, p. 5268 - 5271 (2016)
Stoichiometric C-H bond activation of arenes mediated by iron carbonyls was reported by Pauson as early as in 1965, yet the catalytic C-H transformations have not been developed. Herein, an iron-catalyzed annulation of N-H imines and internal alkynes to furnish cis-3,4-dihydroisoquinolines is described, and represents the first iron-carbonyl-catalyzed C-H activation reaction of arenes. Remarkablely, this is also the first redox-neutral [4+2] annulation of imines and alkynes proceeding by C-H activation. The reaction also features only cis stereoselectivity and excellent atom economy as neither base, nor external ligand, nor additive is required. Experimental and theoretical studies reveal an oxidative addition mechanism for C-H bond activation to afford a dinuclear ferracycle and a synergetic diiron-promoted H-transfer to the alkyne as the turnover-determining step. Double dose of iron: The titled redox-neutral [4+2] annulations to furnish cis-3,4-dihydroisoquinolines were achieved by using iron catalysis. Mechanistic studies show the synergy of dinuclear iron in the C-H bond activation and turnover-limiting hydrogen-transfer steps. The reaction demonstrates excellent atom economy and exclusive cis stereoselectivity.
Ti?Pd Alloys as Heterogeneous Catalysts for the Hydrogen Autotransfer Reaction and Catalytic Improvement by Hydrogenation Effects
Takahashi, Yuya,Kondo, Ryota,Utsunomiya, Masayoshi,Suzuki, Takeyuki,Takeshita, Hiroyuki T.,Obora, Yasushi
, p. 2432 - 2437 (2019)
Ti?Pd alloys were investigated as heterogeneous catalysts for hydrogen autotransfer reactions. This is the first reported study of alloys as catalysts for hydrogen-borrowing reactions using alcohols. We improved the catalytic activities of alloys by increasing their specific surface areas via a hydrogenation?powdering process. The reactivities and selectivities of hydrogenated Ti?Pd alloys [Ti?Pd(Hy)] were higher than those of non-hydrogenated alloy catalysts in N-alkylation by hydrogen autotransfer using alcohols. A plausible catalytic cycle is proposed based on control studies and deuterium labelling experiments.
Desulfurization and H-migration of secondary thioamides catalyzed by an iron complex to yield imines and their reaction mechanism
Fukumoto, Kozo,Sakai, Akane,Hayasaka, Kazumasa,Nakazawa, Hiroshi
, p. 2889 - 2892 (2013)
Secondary thioamides were converted into imines as the major products using hydrosilane in the presence of an iron catalyst. An iron carbene complex with a silyl thiolato ligand was isolated as one of the intermediates of the catalytic cycle and was characterized by X-ray analysis.
Zirconium-mediated intramolecular coupling reactions of unsaturated anilines. Diastereoselective synthesis of azetidines
Barluenga, Jose,Sanz, Roberto,Fananas, Francisco J.
, p. 5953 - 5958 (1997)
Imine complexes of zirconocene, generated by a β-hydrogen abstraction process, which possess a carbon-carbon multiple bond, undergo inter- or intramolecular carbometalation to afford 1,4-cyclohexanediamine or cycloalkylaniline derivatives depending on the relative position of the unsaturated moiety with respect to the imine complex. A new diastereoselective synthesis of azetidines has been developed by treatment of azazirconacyclopentanes with iodine.
Practical and simple synthesis of substituted quinolines by an HCL-DMSO system on a large scale: Remarkable effect of the chloride ion
Tanaka, Shin-Ya,Yasuda, Makoto,Baba, Akio
, p. 800 - 803 (2006)
A variety of substituted quinolines are synthesized from imines and enolizable carbonyl compounds under aerobic conditions, in which only water is a byproduct. In DMSO, a catalytic amount of HCl activates carbonyl compounds quite effectively to give the quinolines. A simple and practical procedure is demonstrated on a large scale.
Titanium promoted reduction of imines with Grignards, silanes, and zinc: Identification of a new mechanism with silanes
Kumar, Akshai,Pandiakumar, Arun Kumar,Samuelson
, p. 3185 - 3190 (2014)
Aldimines react with reducing agents, such as Grignards, phenylsilane or zinc in the presence of titanium(IV) isopropoxide to form amines and reductively coupled imines (diamines). Using deuterium labeled reagents, the mechanism of reduction to form amine
Direct electrochemical reductive amination between aldehydes and amines with a H/D-donor solvent
Chen, Lu,Hong, Huanliang,Hu, Jinhui,Huang, Yubing,Li, Yibiao,Liang, Gen,Pu, Suyun,Zhu, Zhongzhi,Zou, Zirong
, p. 5832 - 5837 (2020)
A novel electrochemical synthesis protocol has been achieved for reductive amination between aldehydes and amines in undivided cells at room temperature. Under metal-free and external-reductant-free electrolysis conditions, various important secondary amine products are obtained in moderate-to-high yields. Deuterium-labeling experiments have demonstrated that low-toxicity DMSO acts both as a solvent and a H-donor in the reaction. On this basis, various deuterium-labeled products with good-to-excellent D-incorporation have been synthesized by using DMSO-d6 as a solvent. Furthermore, a molecule with GR-antagonistic activity has been synthesized through further sulfonylation.
Isomerization of meso diamines into their C2 symmetrical d,l isomers
Alexakis, Alexandre,Aujard, Isabelle,Mangeney, Pierre
, p. 875 - 876 (1998)
An efficient isomerization method is disclosed which allows the obtention of the useful d,l isomers of C2 symmetrical diamines, starting from their meso isomer.
Geometric isomerization and geometry controlled catalytic alcohol aminations of ruthenium hydride compounds containing bidentate pyrrolyl-imines
Li, Yong-Jie,Lai, Hsuan-Ting,Hu, Ching-Han,Chen, Jie-Hong,Lin, Chia-Her,Huang, Jui-Hsien
, (2019)
A series of ruthenium hydride compounds containing bidentate pyrrole-imine ligands were synthesized and characterized and their properties were fully studied. Reacting [C4H3NH-(2-CH=N-R) (L1H, R = CH2-2-furanyl; L2H, R = CH2-morpholine; L3H, R = CH2-2-pyridyl) with one equivalent of n-BuLi afforded the corresponding lithium reagents (LiL1～LiL3). Combining RuHCl(CO)(PPh3)2 with LiL1～LiL3 in THF at 0 °C with stirring at room temperature for 12 h generated pure trans-Pyr-Ru-H 1–3 in moderate yields after repeated fractional recrystallization. When the reactions were performed at reflux temperature, pure cis-Pyr-Ru-H 1–3 were obtained by fractional recrystallization in relatively high yields. A thermal isomerization study showed that pure cis-Pyr-Ru-H 1–3 and trans-Pyr-Ru-H 1–3 can be interconverted in THF after refluxing and equilibrium was attained. Reacting a bulkier ligand [C4H3NLi-(2-CH=N-tBu)] (LiL4) with one equivalent RuHCl(CO)(PPh3)3 at room temperature afforded only cis-Pyr-Ru-H 4 after purification. No trans-Pyr-Ru-H 4 was observed, indicating the bulkier t-butyl group of the L4 ligand altered the stability of cis- and trans-Pyr-Ru-H 4. A catalytic alcohol amination study showed the cis forms of Pyr-Ru-H were the active catalysts for converting benzyl alcohol to N-benzylaniline.
