23068-45-3Relevant academic research and scientific papers
A BEt3-Base catalyst for amide reduction with silane
Yao, Wubing,Fang, Huaquan,He, Qiaoxing,Peng, Dongjie,Liu, Guixia,Huang, Zheng
, (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.
A BEt3-Base Catalyst for Amide Reduction with Silane
Yao, Wubing,Fang, Huaquan,He, Qiaoxing,Peng, Dongjie,Liu, Guixia,Huang, Zheng
, p. 6084 - 6093 (2019/05/24)
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.
Direct Reductive N-Functionalization of Aliphatic Nitro Compounds
Rauser, Marian,Ascheberg, Christoph,Niggemann, Meike
, p. 3970 - 3974 (2018/02/26)
The first general protocol for the direct reductive N-functionalization of aliphatic nitro compounds is presented. The nitro group is partially reduced to a nitrenoid, with a mild and readily available combination of B2pin2 and zinc organyls. Thereby, the formation of an unstable nitroso intermediate is avoided, which has so far severely limited reductive transformations of aliphatic nitro compounds. The reaction is concluded by an electrophilic amination of zinc organyls.
Colloid and nanosized catalysts in organic synthesis: XIV. Reductive amination and amidation of carbonitriles catalyzed by nickel nanoparticles
Popov, Yu. V.,Mokhov,Shcherbakova
, p. 798 - 805 (2016/06/13)
Hydrogenation of carbonitriles catalyzed by nickel nanoparticles in the presence of primary amines led to the predominant formation of unsymmetrical secondary amines. In the presence of secondary amines hydrogenation of nitrites provided enamines as main products. Hydrogenation of nitriles in the presence of formamide or acetamide afforded formyl or acetyl derivatives of primary amines.
Ruthenium-catalyzed N-alkylation of amines with alcohols under mild conditions using the borrowing hydrogen methodology
Enyong, Arrey B.,Moasser, Bahram
, p. 7553 - 7563 (2014/09/17)
Using a simple amino amide ligand, ruthenium-catalyzed one-pot alkylation of primary and secondary amines with simple alcohols was carried out under a wide range of conditions. Using the alcohol as solvent, alkylation was achieved under mild conditions, even as low as room temperature. Reactions occurred with high conversion and selectivity in many cases. Reactions can also be carried out at high temperatures in organic solvent with high selectivity using stoichiometric amounts of the alcohol.
Pt/C catalysed direct reductive amination of nitriles with primary amines in a continuous flow multichannel microreactor
Sharma, Sumeet K.,Lynch, James,Sobolewska, Anna M.,Plucinski, Pawel,Watson, Robert J.,Williams, Jonathan M. J.
, p. 85 - 88 (2013/04/10)
Aliphatic and aromatic secondary amines were synthesised selectively by one pot reductive amination of nitriles with primary amines using Pt/C (3% by weight) catalyst in a continuous flow multichannel microreactor. Molecular hydrogen was used as a clean reducing agent at moderate reaction conditions. The Royal Society of Chemistry 2013.
Selective N-alkylation of amines using nitriles under hydrogenation conditions: Facile synthesis of secondary and tertiary amines
Ikawa, Takashi,Fujita, Yuki,Mizusaki, Tomoteru,Betsuin, Sae,Takamatsu, Haruki,Maegawa, Tomohiro,Monguchi, Yasunari,Sajiki, Hironao
supporting information; experimental part, p. 293 - 304 (2012/02/01)
Nitriles were found to be highly effective alkylating reagents for the selective N-alkylation of amines under catalytic hydrogenation conditions. For the aromatic primary amines, the corresponding secondary amines were selectively obtained under Pd/C-catalyzed hydrogenation conditions. Although the use of electron poor aromatic amines or bulky nitriles showed a lower reactivity toward the reductive alkylation, the addition of NH4OAc enhanced the reactivity to give secondary aromatic amines in good to excellent yields. Under the same reaction conditions, aromatic nitro compounds instead of the aromatic primary amines could be directly transformed into secondary amines via a domino reaction involving the one-pot hydrogenation of the nitro group and the reductive alkylation of the amines. While aliphatic amines were effectively converted to the corresponding tertiary amines under Pd/C-catalyzed conditions, Rh/C was a highly effective catalyst for the N-monoalkylation of aliphatic primary amines without over-alkylation to the tertiary amines. Furthermore, the combination of the Rh/C-catalyzed N-monoalkylation of the aliphatic primary amines and additional Pd/C-catalyzed alkylation of the resulting secondary aliphatic amines could selectively prepare aliphatic tertiary amines possessing three different alkyl groups. According to the mechanistic studies, it seems reasonable to conclude that nitriles were reduced to aldimines before the nucleophilic attack of the amine during the first step of the reaction.
Controlled and chemoselective reduction of secondary amides
Pelletier, Guillaume,Bechara, William S.,Charette, Andre B.
supporting information; experimental part, p. 12817 - 12819 (2010/11/05)
This communication describes a metal-free methodology involving an efficient and controlled reduction of secondary amides to imines, aldehydes, and amines in good to excellent yields under ambient pressure and temperature. The process includes a chemoselective activation of a secondary amide with triflic anhydride in the presence of 2-fluoropyridine. The electrophilic activated amide can then be reduced to the corresponding iminium using triethylsilane, a cheap, rather inert, and commercially available reagent. Imines can be isolated after a basic workup or readily transformed to the aldehydes following an acidic workup. The amine moiety can be accessed via a sequential reductive amination by the addition of silane and Hantzsch ester hydride in a one-pot reaction. Moreover, this reduction tolerates various functional groups that are usually reactive under reductive conditions and is very selective to secondary amides.
A highly active catalyst supported molecular sieves-NaHCO3 mixture for the selective and advantageous N-monoalkylation of amines
Das, Asish R.,Medda, Arunima,Singha, Raghunath,Guchhait, Nikhil
experimental part, p. 841 - 848 (2010/06/01)
Amines are mono-N-alkylated by alkylmesylates in the presence of catalyst supported molecular sieves-NaHCO3 mixture in a regioselective, chemoselective and non-toxic process. Observed chemoselectivity is supported by 'DFT'.
Monoalkylation of primary amines and N-sulfinylamides
García Ruano, José Luis,Parra, Alejandro,Alemán, José,Yuste, Francisco,Mastranzo, Virginia M.
supporting information; experimental part, p. 404 - 406 (2009/05/06)
An efficient monoalkylation of primary amines with primary or secondary alcohols catalyzed by Ra-Ni under mild conditions is described. The Royal Society of Chemistry.
