68950-92-5Relevant academic research and scientific papers
Tungsten-Catalyzed Direct N-Alkylation of Anilines with Alcohols
Lan, Xiao-Bing,Ye, Zongren,Yang, Chenhui,Li, Weikang,Liu, Jiahao,Huang, Ming,Liu, Yan,Ke, Zhuofeng
, p. 860 - 865 (2021/01/18)
The implementation of non-noble metals mediated chemistry is a major goal in homogeneous catalysis. Borrowing hydrogen/hydrogen autotransfer (BH/HA) reaction, as a straightforward and sustainable synthetic method, has attracted considerable attention in the development of non-noble metal catalysts. Herein, we report a tungsten-catalyzed N-alkylation reaction of anilines with primary alcohols via BH/HA. This phosphine-free W(phen)(CO)4 (phen=1,10-phenthroline) system was demonstrated as a practical and easily accessible in-situ catalysis for a broad range of amines and alcohols (up to 49 examples, including 16 previously undisclosed products). Notably, this tungsten system can tolerate numerous functional groups, especially the challenging substrates with sterically hindered substituents, or heteroatoms. Mechanistic insights based on experimental and computational studies are also provided.
Convenient and Reusable Manganese-Based Nanocatalyst for Amination of Alcohols
Subaramanian, Murugan,Ramar, Palmurukan M.,Sivakumar, Ganesan,Kadam, Ravishankar G.,Petr, Martin,Zboril, Radek,Gawande, Manoj B.,Balaraman, Ekambaram
, p. 4334 - 4341 (2021/08/25)
The development of new sustainable nanocatalytic systems for green chemical synthesis is a growing area in chemical science. Herein, a reusable heterogeneous N-doped graphene-based manganese nanocatalyst (Mn@NrGO) for selective N-alkylation of amines with alcohols is described. Mechanistic studies illustrate that the catalytic reaction follows a domino dehydrogenation-condensation-hydrogenation sequence of alcohols and amines with the formation of water as the sole by-product. The scope of the reaction is extended to the synthesis of pharmaceutically important N-alkylated amine intermediates. The heterogeneous nature of the catalyst made it easy to separate for long-term performance, and the recycling study revealed that the catalyst was robust and retained its activity after several recycling experiments.
Alcohol Amination Catalyzed by Copper Powder as a Self-Supported Catalyst
Wu, Yajuan,Huang, Yongji,Dai, Xingchao,Shi, Feng
, p. 3185 - 3191 (2018/11/30)
Catalytic alcohol amination is a sustainable reaction for N-alkyl amine synthesis. Homogeneous and supported copper catalysts have long been studied for this reaction and have given some impressive results. In this study, copper powder is found to behave as an active catalyst for alcohol amination, giving better catalytic performance than metal-oxide-supported nanocopper catalysts. Catalyst characterization suggests that the copper powder can be considered as a self-supported nanocopper catalyst (i.e., nanocopper supported on copper particles). These results might promote the study of unsupported transition metal powders in sustainable catalytic reactions.
An Efficient Metal-Free Method for the Denitrosation of Aryl N-Nitrosamines at Room Temperature
Chaudhary, Priyanka,Korde, Rishi,Gupta, Surabhi,Sureshbabu, Popuri,Sabiah, Shahulhameed,Kandasamy, Jeyakumar
supporting information, p. 556 - 561 (2017/11/13)
A simple and practical method for the denitrosation of aryl N-nitrosamines to secondary amines is reported under metal-free conditions using iodine and triethylsilane. Several reduction-susceptible functional groups such as alkene, alkyne, nitrile, nitro, aldehyde, ketone and ester were found to be very stable during the denitrosation, which is remarkable. Broad substrate scope, room temperature reactions and excellent yields are the additional features of the current methodology. (Figure presented.).
Efficient and Selective Hydrosilylation of Secondary and Tertiary Amides Catalyzed by an Iridium(III) Metallacycle: Development and Mechanistic Investigation
Corre, Yann,Trivelli, Xavier,Capet, Frédéric,Djukic, Jean-Pierre,Agbossou-Niedercorn, Francine,Michon, Christophe
, p. 2009 - 2017 (2017/06/13)
Readily accessible cationic IrIII metallacycles catalyze efficiently the chemoselective hydrosilylation of tertiary and secondary amides to amines. The catalyst described herein operates at low loadings using inexpensive 1,1,3,3-tetramethyldisiloxane and allows fast reactions with high yields, selectivities, and turnover numbers. A transient iminium intermediate has been observed for the first time by using mass spectrometry, and the activation of the catalyst and the silane reagent have been studied by using DFT calculations. These fundamental insights support the present and future improvements of IrIII metallacycles through proper ligand modifications and enable further broad applications of catalysts based on metallacycles.
Base-assisted, copper-catalyzed N-arylation of (benz)imidazoles and amines with diarylborinic acids
Guan, Changwei,Feng, Yuanyuan,Zou, Gang,Tang, Jie
, p. 6906 - 6913 (2017/11/03)
N-Arylation of (benz)imidazoles and amines with diarylborinic acids as cost-effective aryl source has been efficiently effected via Cu(OAc)2-catalyzed Chan-Lam coupling in assistance of tetramethylethylenediamine (TMEDA) in methanol and pyridine (Py) in dichloromethane, respectively, in air at room temperature. The diarylborinic acids could be well accommodated by the Chan-Lam coupling oxidative conditions containing a proper combination of bases and solvents. The steric hindrance appeared to affect the copper-catalyzed N-arylation using the high-order arylboron reagent more significantly than the electronic factors, especially for low reactive anilines and aliphatic amines.
Efficient hydrosilylation of imines using catalysts based on iridium(iii) metallacycles
Corre,Iali,Hamdaoui,Trivelli,Djukic,Agbossou-Niedercorn,Michon
, p. 1452 - 1458 (2015/04/14)
Ir(iii) metallacycles were applied as catalysts for the hydrosilylation of various ketimines and aldimines with sodium tetrakis[(3,5-trifluoromethyl)phenyl]borate, NaBArF24, as an additive. By using a slight excess of the organosilane reagent, the reactions proceeded rapidly and efficiently, at low catalyst loadings and at room temperature. Several examples of cationic Ir(iii) catalysts could be synthesised, characterized and tested. In situ-generated catalysts proved to be more active as compared to isolated ones and species with non-coordinating BArF24 counterion gave the highest catalytic activities.
Pyrrolidine-3-carboxylic acids as endothelin antagonists. 4. Side chain conformational restriction leads to ET(B) selectivity
Von Geldern, Thomas W.,Tasker, Andrew S.,Sorensen, Bryan K.,Winn, Martin,Szczepankiewicz, Bruce G.,Dixon, Douglas B.,Chiou, William J.,Wang, Liming,Wessale, Jerry L.,Adler, Andy,Marsh, Kennan C.,Nguyen, Bach,Opgenorth, Terry J.
, p. 3668 - 3678 (2007/10/03)
When the dialkylacetamide side chain of the ETA-selective antagonist ABT-627 is replaced with a 2,6-dialkylacetanilide, the resultant analogues show a complete reversal of receptor selectivity, preferring ETB over ETA. By optimizing the aniline substitution pattern, as well as the alkoxy group on the 2-aryl substituent, it is possible to prepare antagonists with subnanomolar affinity for ETB and with selectivities in excess of 4000-fold. A number of these compounds also show promising pharmacokinetic profiles; a useful balance of properties is found in A-192621 (38). Pharmacology studies with A-192621 serve to reveal the role of the ETB receptor in modulating blood pressure; the observed hypertensive response to persistent ETB blockade is consistent with previous postulates and indicates that ETB-selective antagonists may not be suitable as agents for long-term systemic therapy.
