scholarly journals Reductive amination with zinc powder in aqueous media

2011 ◽  
Vol 7 ◽  
pp. 1095-1099 ◽  
Author(s):  
Giovanni B Giovenzana ◽  
Daniela Imperio ◽  
Andrea Penoni ◽  
Giovanni Palmisano
Keyword(s):  
Reductive Amination ◽  
Aqueous Media ◽  
Zinc Powder ◽  
Alkaline Media ◽  
Secondary Amines ◽  
Primary Amines ◽  
Complex Hydrides

Zinc powder in aqueous alkaline media was employed to perform reductive amination of aldehydes with primary amines. The corresponding secondary amines were obtained in good yields along with minor amounts of hydrodimerization byproducts. The protocol is a green alternative to the use of complex hydrides in chlorinated or highly flammable solvents.

Acceptorless amine dehydrogenation and transamination using Pd-doped layered double hydroxides

2018 ◽  
Author(s):  
Diana Ainembabazi ◽  
Nan An ◽  
Jinesh Manayil ◽  
Kare Wilson ◽  
Adam Lee ◽  
...  
Keyword(s):  
Layered Double Hydroxides ◽  
Oxidation States ◽  
Secondary Amines ◽  
Primary Amines ◽  
Acid Dissolution ◽  
Oxidative Amination ◽  
Strong Function ◽  
Excellent Activity ◽  
High Yields ◽  
Double Hydroxides

<div> <p>The synthesis, characterization, and activity of Pd-doped layered double hydroxides (Pd-LDHs) for for acceptorless amine dehydrogenation is reported. These multifunctional catalysts comprise Brønsted basic and Lewis acidic surface sites that stabilize Pd species in 0, 2+, and 4+ oxidation states. Pd speciation and corresponding cataytic performance is a strong function of metal loading. Excellent activity is observed for the oxidative transamination of primary amines and acceptorless dehydrogenation of secondary amines to secondary imines using a low Pd loading (0.5 mol%), without the need for oxidants. N-heterocycles, such as indoline, 1,2,3,4-tetrahydroquinoline, and piperidine, are dehydrogenated to the corresponding aromatics with high yields. The relative yields of secondary imines are proportional to the calculated free energy of reaction, while yields for oxidative amination correlate with the electrophilicity of primary imine intermediates. Reversible amine dehydrogenation and imine hydrogenation determine the relative imine:amine selectivity. Poisoning tests evidence that Pd-LDHs operate heterogeneously, with negligible metal leaching; catalysts can be regenerated by acid dissolution and re-precipitation.</p> </div> <br>

Cobalt encapsulated in N‑doped graphene sheet for one-pot reductive amination to synthesize secondary amines

2021 ◽  
Vol 505 ◽  
pp. 111504
Author(s):  
Lin Liu ◽  
Wenxiu Li ◽  
Ran Qi ◽  
Qingqing Zhu ◽  
Jing Li ◽  
...  
Keyword(s):  
Graphene Sheet ◽  
Reductive Amination ◽  
Secondary Amines ◽  
One Pot ◽  
Doped Graphene

scholarly journals Facile Synthesis of COF-Supported Reduced Pd-Based Catalyst for One-Pot Reductive Amination of Aldehydes

Catalysts ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 287
Author(s):  
Jianguo Liu ◽  
Mingyue Zhang ◽  
Longlong Ma
Keyword(s):  
Heterogeneous Catalysts ◽  
Reductive Amination ◽  
Secondary Amines ◽  
Metallic State ◽  
One Pot ◽  
Effective Synthesis ◽  
Pharmaceutical Industries ◽  
The One ◽  
Heterocyclic Aldehydes ◽  
Supported Pd

Dibenzylamine motifs are an important class of crucial organic compounds and are widely used in fine chemical and pharmaceutical industries. The development of the efficient, economical, and environmentally friendly synthesis of amines using transition metal-based heterogeneous catalysts remains both desirable and challenging. Herein, we prepared the covalent organic framework (COF)-supported heterogeneous reduced COF-supported Pd-based catalyst and used it for the one-pot reductive amination of aldehydes. There are both Pd metallic state and oxidated Pdσ+ in the catalysts. Furthermore, in the presence of the reduced COF-supported Pd-based catalyst, many aromatic, aliphatic, and heterocyclic aldehydes with various functional groups substituted were converted to their corresponding amines products in good to excellent selectivity (up to 91%) under mild reaction conditions (70 °C, 2 h, NH3, 20 bar H2). This work expands the covalent organic frameworks for the material family and its support catalyst, opening up new catalytic applications in the economical, practical, and effective synthesis of secondary amines.

Cyclic amidines derived from benz[c,d]indole and 4,5-dihydro-3H-1-benzazepine including some related compounds: Synthesis and pharmacological screening

1985 ◽  
Vol 50 (8) ◽  
pp. 1888-1898 ◽  
Author(s):  
Miroslav Protiva ◽  
Zdeněk Šedivý ◽  
Jiří Holubek ◽  
Emil Svátek ◽  
Jiří Němec
Keyword(s):  
Titanium Tetrachloride ◽  
Aqueous Sodium Hydroxide ◽  
Secondary Amines ◽  
Primary Amines ◽  
Open Chain ◽  
Lithium Aluminium ◽  
Pharmacological Screening ◽  
Antiinflammatory Effects ◽  
Related Compounds ◽  
Sodium Amide

Reactions of naphthostyril (I) with primary and secondary amines and titanium tetrachloride afforded cyclic amidines III-IX. Hydrogenation of I on Pd-C resulted in the 6,7,8,8a-tetrahydro derivative X which gave by treatment with sodium amide and 3-dimethylaminopropyl chloride the N-(aminoalkyl) compound XI. Reduction of I and its N-methyl derivative II with sodium amalgam in aqueous sodium hydroxide gave the 2a,3,4,5-tetrahydro derivatives XII and XIII. Reaction of XIII with sodium amide and 3-dimethylaminopropyl chloride afforded the 2a-(aminoalkyl) compound XIV. 1,3,4,5-Tetrahydro-1-benzazepin-2-one (XV) treated with primary amines and titanium tetrachloride gave the amidines XVI-XVIII. 3-Methyl-7,8,9,9a-tetrahydro-1H-benz[d,e]isoquinoline (XIX) was reduced with sodium borohydride to compound XX which was alkylated with propargyl bromide to 1-methyl-2-propargyl-2,3,3a,4,5,6-hexahydro-1H-benz[d,e]isoquinoline (XXI). An attempt to prepare the 2-(2-phenylethyl) analogue by treatment of compound XX with phenylacetyl chloride and by the following reduction with lithium aluminium hydride resulted in the open-chain amine XXII. The lactams I, II, X, and XIII showed some discoordinating, hypothermic, peripheral vasodilating, hyperglycaemic, diuretic and antiinflammatory effects. The amidines III-IX and XVI-XVIII had local anaesthetic, slight hypotensive, antiarrhythmic, peripheral myorelaxant, papaverine-like spasmolytic and thiopental potentiating effects.

scholarly journals Ureido Functionalization through Amine-Urea Transamidation under Mild Reaction Conditions

Polymers ◽  
2021 ◽  
Vol 13 (10) ◽  
pp. 1583
Author(s):  
Natalia Guerrero-Alburquerque ◽  
Shanyu Zhao ◽  
Daniel Rentsch ◽  
Matthias M. Koebel ◽  
Marco Lattuada ◽  
...  
Keyword(s):  
Aqueous Media ◽  
Reaction Times ◽  
Reaction Rates ◽  
Secondary Amines ◽  
Isocyanic Acid ◽  
Advantages And Disadvantages ◽  
Major Disadvantage ◽  
Wide Range ◽  
Potential Alternative ◽  
Full Conversion

Ureido-functionalized compounds play an indispensable role in important biochemical processes, as well as chemical synthesis and production. Isocyanates, and KOCN in particular, are the preferred reagents for the ureido functionalization of amine-bearing compounds. In this study, we evaluate the potential of urea as a reagent to graft ureido groups onto amines at relatively low temperatures (<100 °C) in aqueous media. Urea is an inexpensive, non-toxic and biocompatible potential alternative to KOCN for ureido functionalization. From as early as 1864, urea was the go-to reagent for polyurea polycondensation, before falling into disuse after the advent of isocyanate chemistry. We systematically re-investigate the advantages and disadvantages of urea for amine transamidation. High ureido-functionalization conversion was obtained for a wide range of substrates, including primary and secondary amines and amino acids. Reaction times are nearly independent of substrate and pH, but excess urea is required for practically feasible reaction rates. Near full conversion of amines into ureido can be achieved within 10 h at 90 °C and within 24 h at 80 °C, and much slower reaction rates were determined at lower temperatures. The importance of the urea/amine ratio and the temperature dependence of the reaction rates indicate that urea decomposition into an isocyanic acid or a carbamate intermediate is the rate-limiting step. The presence of water leads to a modest increase in reaction rates, but the full conversion of amino groups into ureido groups is also possible in the absence of water in neat alcohol, consistent with a reaction mechanism mediated by an isocyanic acid intermediate (where the water assists in the proton transfer). Hence, the reaction with urea avoids the use of toxic isocyanate reagents by in situ generation of the reactive isocyanate intermediate, but the requirement to separate the excess urea from the reaction product remains a major disadvantage.

Direct reductive amination of aldehydes using lithium-arene(cat.) as reducing system. A simple one-pot procedure for the synthesis of secondary amines

2012 ◽  
Vol 53 (25) ◽  
pp. 3156-3160 ◽  
Author(s):  
Fabiana Nador ◽  
Yanina Moglie ◽  
Andrés Ciolino ◽  
Adriana Pierini ◽  
Viviana Dorn ◽  
...  
Keyword(s):  
Reductive Amination ◽  
Secondary Amines ◽  
One Pot ◽  
System A

Primary Amines by Transfer Hydrogenative Reductive Amination of Ketones by Using Cyclometalated IrIIICatalysts

2013 ◽  
Vol 20 (1) ◽  
pp. 245-252 ◽  
Author(s):  
Dinesh Talwar ◽  
Noemí Poyatos Salguero ◽  
Craig M. Robertson ◽  
Jianliang Xiao
Keyword(s):  
Reductive Amination ◽  
Primary Amines

Ambient-Temperature Synthesis of Primary Amines via Reductive Amination of Carbonyl Compounds

ACS Catalysis ◽  
2020 ◽  
Vol 10 (14) ◽  
pp. 7763-7772 ◽  
Author(s):  
Chao Xie ◽  
Jinliang Song ◽  
Manli Hua ◽  
Yue Hu ◽  
Xin Huang ◽  
...  
Keyword(s):  
Ambient Temperature ◽  
Carbonyl Compounds ◽  
Reductive Amination ◽  
Primary Amines ◽  
Temperature Synthesis

Titration syntheses of polyaminosubstituted phthalocyanines via nucleophilic aromatic substitutions on zinc(II) 1,2,3,4,8,9,10,11,15,16,17,18,22,23,24,25-hexadecafluorophthalocyanine

2007 ◽  
Vol 11 (07) ◽  
pp. 537-546 ◽  
Author(s):  
Clifford C. Leznoff ◽  
Annette Hiebert ◽  
Sibel Ok
Keyword(s):  
Amino Acids ◽  
Chain Length ◽  
Secondary Amines ◽  
Primary Amines ◽  
Tertiary Butyl ◽  
Butyl Esters ◽  
Mild Conditions ◽  
Nucleophilic Aromatic Substitutions

Primary amines, secondary amines and tertiary butyl esters of amino acids are used as nucleophiles with zinc(II) hexadecafluorophthalocyanine to provide mixtures of mono and disubstituted fluorinated phthalocyanines under mild conditions, or polyaminosubstituted phthalocyanines when using the amines as solvents. Diamines give cyclic substituted phthalocyanines, binuclear or trinuclear phthalocyanines or mixtures of both types, depending on the chain length or structure of the diamine.

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