622-29-7Relevant articles and documents
Luminescent monocyclometalated cationic gold(iii) complexes: Synthesis, photophysical characterization and catalytic investigations
Zehnder, Thomas N.,Blacque, Olivier,Venkatesan, Koushik
, p. 11959 - 11972 (2014)
Stable, luminescent, and cationic monocyclometalated gold(iii) monoaryl complexes of the type [(ppy)Au(FMes)(L)]+[OTf]- [L = 4-phenylpyridine (3), quinoline (4), 4-fluoroaniline (5), P(OMe)3 (6), PPh3 (7)], bearing different ancillary ligands, synthesized starting from the precursor complex [(ppy)Au(FMes)(OH2)] +[OTf]- (2) are reported. The preliminary assignment of the structure of the complexes by various nuclear magnetic resonance spectroscopy techniques and elemental analysis has been further corroborated by single-crystal X-ray diffraction studies. The complexes exhibit room temperature phosphorescence in solution, in neat solids and in doped PMMA films. Detailed photophysical investigations of the complexes in solution, in neat solids and in PMMA films revealed the successful tuning of the emission quantum yield ( p) based on the electronic properties of the ancillary ligands. The catalytic photo-oxidation of benzylic amines to their corresponding imines using molecular oxygen as the oxidant was successfully achieved in the presence of the luminescent Au(iii) complexes. It is also established that the photocatalytic performance was strongly governed by the electronic properties of the ancillary ligands on the photosensitizer as well as by the steric bulk of the substrates. This journal is the Partner Organisations 2014.
Cobalt-catalyzed carbonylation of N-alkylbenzaldimines to 'N-alkylphthalimidines' (=2,3-dihydro-1H-isoindol-1-ones) via tandem C-H activation and cyclocarbonylation
Funk, Jeffrey K.,Yennawar, Hemant,Sen, Ayusman
, p. 1687 - 1695 (2006)
The reaction of N-alkylbenzaldimines with carbon monoxide (CO) in the presence of cobalt (Co) catalysts resulted in the formation of N-alkylphthalimidines (Table 1). Their formation is proposed to occur by C-H activation of the aryl ring, migratory insertion of the hydride species into the benzaldimine functionality, CO coordination, and insertion into the Co-C bond, followed by reductive elimination of the N-alkylphthalimidine and regeneration of the starting Co species (Scheme 4). Deuterium (2H)-labeling NMR studies are consistent with this mechanism (Scheme 5).
Design, Synthesis, and Biological Evaluation of Novel 3-Aminomethylindole Derivatives as Potential Multifunctional Anti-Inflammatory and Neurotrophic Agents
Wang, Wei-Wei,Liu, Ting,Lv, Yu-Meng,Zhang, Wu-Yang,Liu, Zhi-Gang,Gao, Jin-Ming,Li, Ding
, p. 1593 - 1605 (2021/05/31)
The development of multifunctional molecules that are able to simultaneously interact with several pathological components has been considered as a solution to treat the complex pathologies of neurodegenerative diseases. Herein, a series of aminomethylindole derivatives were synthesized, and evaluation of their application for antineuroinflammation and promoting neurite outgrowth was disclosed. Our initial screening showed that most of the compounds potently inhibited lipopolysaccharide (LPS)-stimulated production of NO in microglial cells and potentiated the action of NGF to promote neurite outgrowth of PC12 cells. Interestingly, with outstanding NO/TNF-α production inhibition and neurite outgrowth-promoting activities, compounds 8c and 8g were capable of rescuing cells after injury by H2O2. Their antineuroinflammatory effects were associated with the downregulation of the LPS-induced expression of the inflammatory mediators inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2). Western blotting and immunofluorescence assay results indicated that the mechanism of their antineuroinflammatory actions involved suppression of the MAPK/NF-κB signal pathways. Further studies revealed that another important reason for the high comprehensive antineuroinflammatory activity was the anti-COX-2 capabilities of the compounds. All these results suggest that the potential biochemical multifunctional profiles of the aminomethylindole derivatives provide a new sight for the treatment of neurodegenerative diseases.
Discovery of tert-amine-based RORγt agonists
Qiu, Ruomeng,Yu, Mingcheng,Gong, Juwen,Tian, Jinlong,Huang, Yafei,Wang, Yonghui,Xie, Qiong
, (2021/07/26)
The nuclear receptor retinoic acid receptor-related orphan receptor gamma-t (RORγt) is a transcription factor regulating Th17 cell differentiation and proliferation from naive CD4+ T cells. Since Th17 cells have demonstrated the antitumor efficacy by eliciting remarkable activation of CD8+ T cells, RORγt agonists could be applied as potential small molecule therapeutics for cancer immunotherapy. Based on the previously reported RORγt agonist 1 and its resolved co-crystal structure, a series of new tertiary amines were designed, synthesized and biologically evaluated, yielding optimal moieties with improved chemical properties and biological responses. The combination of these optimal moieties resulted in identification of novel RORγt agonists such as 8b with further elevated RORγt agonism responses at a target-based level as well as in cell-based assays, which provided some structural knowledge for further optimization of RORγt agonists as small molecule therapeutics for cancer immunotherapy.
Photocatalytic Hydrogen Evolution Coupled with Production of Highly Value-Added Organic Chemicals by a Composite Photocatalyst CdIn2S4@MIL-53-SO3Ni1/2
Zhang, Huan-Huan,Zhan, Guo-Peng,Liu, Zi-Kun,Wu, Chuan-De
supporting information, p. 1499 - 1506 (2021/05/06)
Photocatalytic water splitting coupled with the production of highly value-added organic chemicals is of significant importance, which represents a very promising pathway for transforming green solar energy into chemical energy. Herein, we report a composite photocatalyst CdIn2S4@MIL-53-SO3Ni1/2, which is highly efficient on prompting water splitting for the production of H2 in the reduction half-reaction and selective oxidation of organic molecules for the production of highly value-added organic chemicals in the oxidation half-reaction under visible light irradiation. The superior photocatalytic properties of the composite photocatalyst CdIn2S4@MIL-53-SO3Ni1/2 should be ascribed to coating suspended ion catalyst (SIC), consisting of redox-active NiII ions in the anionic pores of coordination network MIL-53-SO3?, on the surface of photoactive CdIn2S4, which endows photogenerated electron-hole pairs separate more efficiently for high rate production of H2 and selective production of highly value-added organic products, demonstrating great potential for practical applications.
Enantioselective Reductive Coupling of Imines Templated by Chiral Diboron
Chen, Dongping,Li, Kaidi,Tang, Wenjun,Xu, Guangqing,Xu, Ronghua,Zhou, Mingkang
supporting information, p. 10337 - 10342 (2020/07/04)
We herein report a general, practical, and highly efficient method for asymmetric synthesis of a wide range of chiral vicinal diamines via reductive coupling of imines templated by chiral diboron. The protocol features high enantioselectivity and stereospecificity, mild reaction conditions, simple operating procedures, use of readily available starting materials, and a broad substrate scope. The method signifies the generality of diboron-enabled [3,3]-sigmatropic rearrangement.
Photocatalytic selective aerobic oxidation of amines to nitriles over Ru/γ-Al2O3: The role of the support surface and the strong imine intermediate adsorption
Zhu, Pengqi,Zhang, Jin,Wang, Jie,Kong, Peng,Wang, Yunwei,Zheng, Zhanfeng
, p. 440 - 449 (2020/02/04)
Hydroxyl coordinated ruthenium dispersed on the surface of γ-Al2O3 can be applied to the selective oxidation of amines with light irradiation and an atmospheric pressure of O2 at room temperature. Sunlight is also an effective light source for the selective aerobic oxidation of primary amines to corresponding nitriles. The high photocatalytic activity and selectivity over Ru/γ-Al2O3 originate from the adsorption of amines and imine intermediates on the abundant surface OH groups of the photocatalyst and further formation of Ru-amide species by ligand exchange of adsorbed amines and imine intermediates with adjacent exposed active Ru sites. Light is introduced to the system successfully via the formation of Ru-amide species, which are used as the light absorption sites of the photocatalytic selective oxidation of amines. Primary amines are directly converted to corresponding nitriles via a two-step oxidative dehydrogenation process.
Photoimmobilized Ni Clusters Boost Photodehydrogenative Coupling of Amines to Imines via Enhanced Hydrogen Evolution Kinetics
Huang, Yi,Li, Huizhi,Li, Mengyang,Li, Yongwang,Liu, Cuibo,Su, Ren,Zhang, Bin
, p. 3904 - 3910 (2020/03/30)
Imines are important precursors for pharmaceutical, agricultural, and synthetic chemistry. The state-of-art synthesis of imines via condensation of amines with aldehydes or ketones often uses homogeneous catalysts and dehydrating agents to promote the elimination of water, which requires huge manpower input for the late-stage purification process and is usually environmentally unfriendly. Photocatalytic synthesis of imines from amines oxidation via the release of hydrogen (H2) is of great promise due to the mild reaction characteristics; however, the efficiency of such a reaction lags due to the missing designed photocatalyst owing to the ambiguous reaction mechanism. Here, we demonstrate that by constructing in situ photoimmobilized Ni clusters on the CdS photocatalyst, the generation of imines is dramatically improved with the rapid release of molecular H2 under visible light illumination. Mechanistic investigation reveals that the adsorption of photogenerated hydrogen atoms during the dehydrogenation of amines is significantly weakened on Ni clusters, thus resulting in fast C-N coupling kinetics for the generation of imines. The photocatalyst presents stable performance with high efficiency. A remarkably apparent quantum efficiency (AQE) of ?44% is realized under 420 nm irradiation for the conversion of 4-methoxybenzylamine within six consecutive runs. Furthermore, a series of primary and secondary amines bearing different functional groups (i.e., heterocyclic, aliphatic, N-heterocycles) that are synthetically challenging by the condensation process can be selectively converted to the corresponding imines, featuring its application prospect.
Stable carbamate pathway towards organic-inorganic hybrid perovskites and aromatic imines
Hur, Nam Hwi,Kim, Sun Joo,Lee, Byeongno,Lee, Kyu Hyung,Lim, Byung Wook,Nam, Wonwoo,Park, Hee Sun,Park, Young Jun
, p. 38055 - 38062 (2020/11/02)
Methyl ammonium methyl carbamate (MAC), formulated as CH3NH3+CH3NHCO2-, was synthesized by reacting liquid methylamine with supercritical CO2, and its structure was refined by single-crystal X-ray diffraction. MAC is a white crystalline salt and is as reactive as methylamine, and is a very efficient alternative to toxic methylamine. We were able to produce hybrid perovskite MAPbI3 (MA = methyl ammonium) by grinding MAC with PbI2 and I2 at room temperature, followed by storing the mixed powder. Moreover, this one-pot method is easily scalable for the large-scale synthesis of MAPbI3 in a small vessel. We have also investigated the reactivity of MAC towards aromatic aldehydes in the absence of solvent. The solventless reactions afforded imines as exclusive products with over 97% yield, which show higher selectivity than the methylamine-based synthesis. Complete conversions were typically accomplished within 3 h at 25 °C. The results of this study emphasize the importance of solid carbamates such as MAC to develop an environmentally friendly process for the synthesis of various amine-based materials on the industrial scale.
A BEt3-Base catalyst for amide reduction with silane
Yao, Wubing,Fang, Huaquan,He, Qiaoxing,Peng, Dongjie,Liu, Guixia,Huang, Zheng
supporting information, (2019/05/22)
Reported herein is the development of a simple but practical catalytic system for the selective reduction of amides with hydrosilane or hydrosiloxane. Low-cost and readily available triethylborane (1.0 M in THF), in combination with a catalytic amount of an alkali metal base, was found to catalyze the reduction of all three amide classes (tertiary, secondary, and primary amides) to form amines under mild conditions. In addition, the selective transformation of secondary amides to aldimines and primary amides to nitriles can also be achieved by using a proper combination of BEt3 and base. The scope of these BEt3-base-catalyzed amide hydrosilylation reactions has been explored in depth. Preliminary results of mechanistic studies suggest a modified Piers' silane Si-H···B activation mode wherein the hydride abstraction by BEt3 is promoted by the coordination of an alkoxide or hydroxide anion to the Si center.
