105909-65-7Relevant academic research and scientific papers
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.
Direct N-Alkylation/Fluoroalkylation of Amines Using Carboxylic Acids via Transition-Metal-Free Catalysis
Lu, Chunlei,Qiu, Zetian,Xuan, Maojie,Huang, Yan,Lou, Yongjia,Zhu, Yiling,Shen, Hao,Lin, Bo-Lin
supporting information, p. 4151 - 4158 (2020/08/21)
A scalable protocol of direct N-mono/di-alkyl/fluoroalkylation of primary/secondary amines has been constructed with various carboxylic acids as coupling agents under the catalysis of a simple air-tolerant inorganic salt, K3PO4. Advantageous features include 100 examples, 10 drugs and drug-like amines, fluorinated complex tertiary amines, gram-scale synthesis and isotope-labelling amine, thus demonstrating the potential applicability in industry of this methodology. The involvement of relatively less reactive silicon-hydride compared with the traditional reactive metal-hydride or boron-hydride species required to reduce the amide intermediates presumably contributes to the remarkable functional group compatibility. (Figure presented.).
One-pot synthesis of amines from biomass resources catalyzed by HReO4
Caetano, Jo?o A. T.,Fernandes, Ana C.
, p. 2494 - 2498 (2018/06/11)
This work describes the one-pot synthesis of furfurylamines from carbohydrates catalyzed by HReO4. These one-pot three-reaction and four-reaction processes allow the conversion of xylose and xylan, respectively, into a large variety of secondary and tertiary amines with good overall yields and chemoselectivity.
Ligand-free Iron(II)-Catalyzed N-Alkylation of Hindered Secondary Arylamines with Non-activated Secondary and Primary Alcohols via a Carbocationic Pathway
Nayal, Onkar S.,Thakur, Maheshwar S.,Kumar, Manoranjan,Kumar, Neeraj,Maurya, Sushil K.
supporting information, p. 730 - 737 (2017/12/26)
Secondary benzylic alcohols represent a challenging class of substrates for N-alkylation of amines. Herein, we describe an iron(II)-catalyzed eco-friendly protocol for N-alkylation of secondary arylamines with secondary benzyl alcohols through a carbocationic pathway instead of the known borrowing hydrogen transfer (BHT) approach. Transiently generated carbocations, produced from alcohols via self-condensation, were coupled with arylamines to provide highly functionalized amine products. The scope of this methodology involves N-alkylation of primary, secondary and heterocyclic amines with primary/secondary benzylic, allylic and heterocyclic alcohols, which are common key structures in numerous pharmaceuticals drugs. The method can also be easily adopted for the amination of various natural products. (Figure presented.).
Efficient Ruthenium(II)-Catalyzed Direct Reductive Amination of Aldehydes under Mild Conditions Using Hydrosilane as the Reductant
Li, Bin,Zheng, Jianxiong,Zeng, Weifeng,Li, Yibiao,Chen, Lu
supporting information, p. 1349 - 1355 (2017/03/11)
A direct reductive amination of aldehydes with anilines is performed with a ruthenium(II)-(arene) catalyst. The [RuCl2(p-cymene)]2/Ph2SiH2 catalytic system is very efficient for the synthesis of secondary amines and tertiary amines in good yields, and is highly chemoselective, tolerating a wide range of functional groups, such as NO2, CN, CO2Me, F, Cl, Br, OMe, Me, furyl and alkyl. We also report an interesting direductive amination of 2-ethylbutanal.
Synthesis of tertiary arylamines: Lewis acid-catalyzed direct reductive: N -alkylation of secondary amines with ketones through an alternative pathway
Nayal, Onkar S.,Thakur, Maheshwar S.,Bhatt, Vinod,Kumar, Manoranjan,Kumar, Neeraj,Singh, Bikram,Sharma, Upendra
supporting information, p. 9648 - 9651 (2016/08/04)
We report herein a highly efficient, tin(ii)/PMHS catalyzed reductive N-alkylation of arylamines with ketones affording tertiary arylamines. A very wide substrate scope was observed for the current catalytic method as all six permutations of ketones/aldehydes/heterocyclic carbonyls and primary/secondary/heterocyclic amines were well tolerated, enabling access to secondary, tertiary and heterocyclic amines. The method is also convenient for the synthesis of N-substituted isoindolinones and phthalazinones via a tandem amination-amidation sequence. Mechanistic investigations revealed a carbocationic pathway instead of an ordinary direct reductive amination pathway.
Chemoselective reductive amination of carbonyl compounds for the synthesis of tertiary amines using SnCl2·2H2O/PMHS/MeOH
Nayal, Onkar S.,Bhatt, Vinod,Sharma, Sushila,Kumar, Neeraj
, p. 5912 - 5918 (2015/06/16)
Stannous chloride catalyzed chemoselective reductive amination of a variety of carbonyl compounds with aromatic amines has been developed for the synthesis of a diverse range of tertiary amines using inexpensive polymethylhydrosiloxane as reducing agent in methanol. The present method is also applicable for the synthesis of secondary amines including heterocyclic ones.
Efficient and chemoselective direct reductive amination of aromatic aldehydes catalyzed by oxo-rhenium complexes containing heterocyclic ligands
Bernardo, Joana R.,Sousa, Sara C.A.,Florindo, Pedro R.,Wolff, Mariusz,Machura, Barbara,Fernandes, Ana C.
, p. 9145 - 9154 (2013/09/24)
This work describes the catalytic activity of 17 oxo-rhenium complexes containing heterocyclic ligands in the direct reductive amination of 4-nitrobenzaldehyde with 4-chloroaniline, using phenylsilane as reducing agent. In general, all of the catalysts tested gave excellent yields of the secondary amine, although, the best result was obtained with the catalytic system PhSiH3/ReOBr2(Hhmpbta)(PPh3) (2.5 mol %). This system was also applied to the synthesis of a large variety of secondary amines in good to excellent yields and tertiary amines in moderate yields, with tolerance of different functional groups.
