33033-90-8Relevant articles and documents
Study on products and reaction paths for synthesis of 3,4-dihydro-2H-3-phenyl-1,3-benzoxazine from phenol, aniline and formaldehyde
Zhang, Cheng-Xi,Deng, Yu-Yuan,Zhang, Yi-Yang,Yang, Po,Gu, Yi
, p. 348 - 352 (2015)
To study the synthesis of 3,4-dihydro-2H-3-phenyl-1,3-benzoxazine (benzoxazine), the reaction paths of phenol, aniline and formaldehyde were investigated by analyzing the synthesis crude products. With the aid of high-performance liquid chromatography (HP
BF3·Et2O as a metal-free catalyst for direct reductive amination of aldehydes with amines using formic acid as a reductant
Fan, Qing-Hua,Liu, Xintong,Luo, Zhenli,Pan, Yixiao,Xu, Lijin,Yang, Ji,Yao, Zhen,Zhang, Xin
supporting information, p. 5205 - 5211 (2021/07/29)
A versatile metal- and base-free direct reductive amination of aldehydes with amines using formic acid as a reductant under the catalysis of inexpensive BF3·Et2O has been developed. A wide range of primary and secondary amines and diversely substituted aldehydes are compatible with this transformation, allowing facile access to various secondary and tertiary amines in high yields with wide functional group tolerance. Moreover, the method is convenient for the late-stage functionalization of bioactive compounds and preparation of commercialized drug molecules and biologically relevant N-heterocycles. The procedure has the advantages of simple operation and workup and easy scale-up, and does not require dry conditions, an inert atmosphere or a water scavenger. Mechanistic studies reveal the involvement of imine activation by BF3and hydride transfer from formic acid.
Ruthenium N-Heterocyclic Carbene Complexes for Chemoselective Reduction of Imines and Reductive Amination of Aldehydes and Ketones
Kathuria, Lakshay,Samuelson, Ashoka G.
, (2020/06/17)
Chemoselective reduction of imines to secondary amines is catalyzed efficiently by tethered and untethered, half-sandwich ruthenium N-heterocyclic carbene (NHC) complexes at room temperature. The untethered Ru-NHC complexes are more efficient as catalysts for the reduction of aldimines and ketimines than the tethered complexes. Using the best untethered complex as a catalyst, electronic and steric demands on the reaction was probed using a series of imines. Chemoselectivity of the catalyst towards imine reduction was tested by performing inter and intramolecular competitive reactions in a variety of ways. The catalyst exhibits a very high TON and TOF under anaerobic conditions.
Method for preparing secondary amine compound through imine hydrogenation reduction
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Paragraph 0042-0045, (2019/12/02)
The invention belongs to the technical field of medical and natural compound chemical intermediates and related chemistry, and provides a method for preparing secondary amine compounds through imine hydrogenation reduction. According to the method, the im
Iron-Catalyzed Nitrene Transfer Reaction of 4-Hydroxystilbenes with Aryl Azides: Synthesis of Imines via C=C Bond Cleavage
Peng, Yi,Fan, Yan-Hui,Li, Si-Yuan,Li, Bin,Xue, Jing,Deng, Qing-Hai
, p. 8389 - 8394 (2019/10/16)
C=C bond breaking to access the C=N bond remains an underdeveloped area. A new protocol for C=C bond cleavage of alkenes under nonoxidative conditions to produce imines via an iron-catalyzed nitrene transfer reaction of 4-hydroxystilbenes with aryl azides is reported. The success of various sequential one-pot reactions reveals that the good compatibility of this method makes it very attractive for synthetic applications. On the basis of experimental observations, a plausible reaction mechanism is also proposed.
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.).
Unprecedented catalytic performance in amine syntheses: Via Pd/g-C3N4 catalyst-assisted transfer hydrogenation
Xu, Xingliang,Luo, Jiajun,Li, Liping,Zhang, Dan,Wang, Yan,Li, Guangshe
supporting information, p. 2038 - 2046 (2018/05/24)
The preparation of amine compounds is very important for both the chemical industry and renewable feedstock processing. Nevertheless, difficulties remain in finding a catalytic system that is sufficiently active and environmentally benign for producing amine compounds. In this work, we report that g-C3N4 nanosheets as support materials can significantly boost the efficiency of Pd nanoparticles for the reduction of nitro compounds to primary amines. Using formic acid as a hydrogen donor and water as a solvent, the optimized 5 wt% Pd/g-C3N4 catalyst exhibited an unprecedented performance in the conversion of nitrobenzene into aniline (achieving almost full conversion with an extremely high turnover frequency of 4770 h-1 at room temperature), yielding the best activity ever reported for heterogeneously catalyzing nitro compound reduction. Pd/g-C3N4 catalyst was also active for the one-pot reductive amination of carbonyl compounds with nitro compounds to obtain the corresponding secondary amines with excellent selectivity (>90%). We proposed that the protic N-H+ and hydridic Pd-H- on Pd/g-C3N4 are the active species for the transfer hydrogenation reaction of nitro compounds. Furthermore, Pd/g-C3N4 catalyst was highly stable with a wide scope in the syntheses of various amine compounds. This work will open up a new approach for the transfer hydrogenations of nitro compounds to produce primary or secondary amines in green chemistry.
One-pot Reductive Amination of Carbonyl Compounds with NaBH4-B(OSO3H)3/SiO2 in Acetonitrile and in Solvent-free Condition
Hamadi, Hosein,Javadi, Samira
, p. 75 - 80 (2017/01/24)
An efficient one-pot procedure for the direct reductive amination of aldehyde and ketones was achieved in the presence of sodium borohydride by using B(OSO3H)3/SiO2(SBSA) as the reusable solid catalyst in acetonitrile and solvent-free conditions. Both aromatic and aliphatic aldehyde reacted well to give the corresponding amines in excellent yields. All the products are known and well-characterized. The catalyst is recoverable and could be easily recycled by filtration and reused several times without any significant loss of its activity. SBSA acts as a dual Br?nsted/Lewis acid that is an air-stable and cost-effective solid acid. [Figure not available: see fulltext.]
Design, synthesis and biological evaluation of GPR55 agonists
Fakhouri, Lara,Cook, Christopher D.,Al-Huniti, Mohammed H.,Console-Bram, Linda M.,Hurst, Dow P.,Spano, Michael B.S.,Nasrallah, Daniel J.,Caron, Marc G.,Barak, Larry S.,Reggio, Patricia H.,Abood, Mary E.,Croatt, Mitchell P.
, p. 4355 - 4367 (2017/07/22)
GPR55, a G protein-coupled receptor, is an attractive target to alleviate inflammatory and neuropathic pain and treat osteoporosis and cancer. Identifying a potent and selective ligand will aid to further establish the specific physiological roles and pharmacology of the receptor. Towards this goal, a targeted library of 22 compounds was synthesized in a modular fashion to obtain structure-activity relationship information. The general route consisted of coupling a variety of p-aminophenyl sulfonamides to isothiocyanates to form acylthioureas. For the synthesis of a known naphthyl ethyl alcohol motif, route modification led to a shorter and more efficient process. The 22 analogues were analyzed for their ability to serve as agonists at GPR55 and valuable information for both ends of the molecule was ascertained.
Direct reductive amination of aldehydes with nitroarenes using bio-renewable formic acid as a hydrogen source
Zhang, Qi,Li, Shu-Shuang,Zhu, Ming-Ming,Liu, Yong-Mei,He, He-Yong,Cao, Yong
supporting information, p. 2507 - 2513 (2016/05/19)
Reductive amination (RA) is one of the most important transformations in organic chemistry. A versatile and sustainable gas-free RA of aldehydes carried out directly with cheaply available nitroarenes using stoichiometric amounts of non-toxic and entirely renewable formic acid (FA) as the terminal reductant is described herein. A single phase rutile titania supported gold (Au/TiO2-R) catalyst is shown to catalyse efficiently this FA-based direct RA in neat water under mild reaction conditions. The broad scope, mild and neutral conditions, together with CO2 and water as environmental harmless byproducts, make this transformation very useful. Moreover, straightforward examples of the direct construction of bioactive heterocyclic compounds containing a benzimidazole motif were achieved through this protocol.
