75567-86-1Relevant academic research and scientific papers
Additive-freeN-methylation of amines with methanol over supported iridium catalyst
Liu, Xiang,Loh, Teck-Peng,Qiang, Wenwen,Wang, Jing,Ye, Sen,Zhu, Longfei
, p. 3364 - 3375 (2021/06/06)
An efficient and versatile zinc oxide-supported iridium (Ir/ZnO) catalyst was developed to catalyze the additive-freeN-methylation of amines with methanol. Mechanistic studies suggested that the high catalytic reactivity is rooted in the small sizes (1.4 nm) of Ir nanoparticles and the high ratio (93%) of oxidized iridium species (IrOx, Ir3+and Ir4+) on the catalyst. Moreover, the delicate cooperation between the IrOxand ZnO support also promoted its high reactivity. The selectivity of this catalyticN-methylation was controllable between dimethylation and monomethylation by carefully tuning the catalyst loading and reaction solvent. Specifically, neat methanol with high catalyst loading (2 mol% Ir) favored the formation ofN,N-dimethylated amine, while the mesitylene/methanol mixture with low catalyst loading (0.5 mol% Ir) was prone to producing mono-N-methylated amines. An environmentally benign continuous flow system with a recycled mode was also developed for the efficient production ofN-methylated amines. With optimal flow rates and amine concentrations, a variety ofN-methylamines were produced with good to excellent yields in this Ir/ZnO-based flow system, providing a starting point for the clean and efficient production ofN-methylamines with this cost-effective chemical process.
Nickel-catalyzed reductive hydroesterification of styrenes using CO 2 and MeOH
Gonzalez-Sebastian, Lucero,Flores-Alamo, Marcos,Garcia, Juventino J.
, p. 8200 - 8207 (2013/02/22)
Complexes [(dippe)Ni(μ-H)]2 (A) (dippe = 1,2-bis-di- isopropylphosphino)ethane) and [(dtbpe)Ni(μ-H)]2 (B) (dtbpe = 1,2-bis-di-tert-butylphospino)ethane) catalyze the reductive hydroesterification of styrenes with the use of CO2 and MeOH. The latter acts as a hydrogen source and as an esterificating agent, to yield the corresponding branched and linear esters in moderate to good yields. In all of the studied reactions the linear esters were obtained in higher amounts than the branched ones. When the hydroesterification reaction was carried out using a stoichiometric metal/substrate ratio, the complexes [(P-P)Ni(CO)2] and [(P-P)Ni(CO3)] (P-P = dippe or dtbpe) were isolated and characterized by standard spectroscopic methods. Compounds [(dtbpe)Ni(CO) 2] and [(dtbpe)Ni(CO3)] were also fully characterized by single-crystal X-ray diffraction.
HKGreen-3: A rhodol-based fluorescent probe for peroxynitrite
Peng, Tao,Yang, Dan
supporting information; experimental part, p. 4932 - 4935 (2010/12/25)
A novel fluorescent probe, HKGreen-3, for sensing peroxynitrite is designed on the basis of the rhodol scaffold and a peroxynitrite-specific oxidation reaction. The probe turns out to be highly sensitive and selective for detecting peroxynitrite in both chemical and biological systems.
Stereoselective hydrocoupling of cinnamic acid esters by electroreduction: Application to asymmetric synthesis of hydrodimers
Kise, Naoki,Iitaka, Shumei,Iwasaki, Keisuke,Ueda, Nasuo
, p. 8305 - 8315 (2007/10/03)
The electroreduction of Ar-substituted methyl cinnamates in acetonitrile gave all-trans cyclized hydrodimers stereoselectively (58-90% de). In all cases, small amounts (2-symmetric dl-3,4-diaryladipic acids and trans-3,4-diarylcyclopentanones. The chiral auxiliary [(1R)-exo]-3-exo-(diphenylmethyl)borneol, prepared from (1R)-(+)-camphor, was highly effective for the stereoselective hydrocoupling of its cinnamates by electroreduction. From the resulting hydrodimers, (3R,4R)-3,4-diaryladipic acid esters and (3R,4R)-3,4-diarylhexane-1,6-diols were synthesized in 87-95% ee.
Amide derivatives and intermediates for the synthesis thereof
-
, (2008/06/13)
Novel compounds which are amide derivatives represented by general formula (I) and medicinal preparations containing the same having an eosinophilic infiltration inhibitory effect based on a potent interferon (α,γ)-inducing activity and an exellent percutaneous absorbability and being efficacious in treating allergic inflammatory diseases such as atopic dermatitis, various tumors and viral diseases. In said formula, each symbol has the following meaning: R1 and R2 : each lower alkyl, etc.; X and Y: independently representing each oxygen, NR4, CR5 etc. (wherein R4 and R5 independently represent each hydrogen, an aromatic group, etc.); Z: an aromatic ring or heterocycle; R3 : hydrogen, lower alkoxy, etc.; g, i and k: independently representing each an integer of from 0 to 6; h, i and l: independently representing each an integer of 0 or 1; m: an integer of from 0 to 5; and n: an integer of from 2 to 12.
SYNTHESIS OF A TRIAD MOLECULAR SYSTEM CONTAINING THE PHOTOSENSITIZER MESOPORPHYRIN II AND A SECONDARY ELECTRON DONOR AND ACCEPTOR FOR MODELING THE PHOTOSYNTHESIS PROCESS
Borovkov, V. V.,Evstigneeva, R. P.,Gribkov, A. A.
, p. 296 - 302 (2007/10/03)
We describe methods for synthesis of a triad molecular system based on mesoporphyrin II with electron-donor and electron-acceptor moieties for modeling the primary stage of charge separation in photosynthesis, differing in the order of addition of the donor and the acceptor.Using fluorescent spectroscopy, we have demonstrated quenching-containing coppounds.Investigation of the triad and its zinc complex by kinetic fluorescent spectroscopy allowed us to determine the electron transfer rate constants for the triad and for its zinc complex.
Mechanism of Charge Transfer in the Molecular DPQ Complex Studied by Time-Resolved Fluorescence Spectroscopy
Borovkov, V. V.,Evstigneeva, R. P.,Struganova, I. A.,Kamalov, V. F.,Toleutaev, B. N.
, p. 6437 - 6440 (2007/10/02)
The pathways of charge separation in the dimethylaniline-mesoporphyrin II-naphthoquinone triad DPQ and its Zn complex were established.The rate constants of electron transfer from P and ZnP to Q were measured to be k = 1.5x109 s-1 and k > 5x1010 s-1, respectively, from the results of picosecond fluorescence spectroscopy.The transformation of the DPQ and DZnPQ triads to the reduced form by NaBH4 treatment results in blocking of the electron-transfer channel from both P and ZnP to Q.The transformation of the DPQ and DZnPQ triads to the reduced forms by NaBH4 results in blocking of the electron-transfer channel from both P and ZnP to Q.The role of structural and conformational changes of triads in the electron-transfer process is discussed.
The Transmission of Substituent-Induced 13C NMR Chemical Shifts in para-Substituted 3-Phenyl Propanoic Acid Methyl Esters
Radeglia, R.,Spassov, S. L.,Stefanova, R.,Simova, S. D.
, p. 934 - 936 (2007/10/02)
Carbon-13 chemical shifts have been measured of para-substituted 3-phenyl propanoic acid methyl esters.The substituent-induced 13C shifts of the side chain were related to Hammett substituent effects by the dual substituent parameter method.The transmission of substituent effects and the factors that influence 13C shifts are discussed. - Keywords: Dual Substituent Parameters, Polar and Steric Interactions, Conformational Energy, 13C NMR Spectra
