The synthesis of α-aryl-α-aminophosphonates and α-aryl-α-aminophosphine oxides by the microwave-assisted Pudovik reaction

A family of α-aryl-α-aminophosphonates and α-aryl-α-aminophosphine oxides was synthesized by the microwave-assisted solvent-free addition of dialkyl phosphites and diphenylphosphine oxide, respectively, to imines formed from benzaldehyde derivatives and primary amines. After optimization, the reactivity was mapped, and the fine mechanism was evaluated by DFT calculations. Two α-aminophosphonates were subjected to an X-ray study revealing a racemic dimer formation made through a N–H···O=P intermolecular hydrogen bridges pair.

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Microwave-assisted synthesis of (aminomethylene)bisphosphine oxides and (aminomethylene)bisphosphonates by a three-component condensation

Beilstein Journal of Organic Chemistry ◽

10.3762/bjoc.12.146 ◽

2016 ◽

Vol 12 ◽

pp. 1493-1502 ◽

Cited By ~ 15

Author(s):

Erika Bálint ◽

Ádám Tajti ◽

Anna Dzielak ◽

Gerhard Hägele ◽

György Keglevich

Keyword(s):

Reaction Mechanism ◽

Practical Method ◽

Solvent Free ◽

Secondary Amines ◽

Primary Amines ◽

Microwave Assisted Synthesis ◽

Diphenylphosphine Oxide ◽

Microwave Assisted ◽

Reactant Pairs ◽

By Products

A practical method was elaborated for the synthesis of (aminomethylene)bisphosphine oxides comprising the catalyst- and solvent-free microwave-assisted three-component condensation of primary amines, triethyl orthoformate and two equivalents of diphenylphosphine oxide. The method is also suitable for the preparation of (aminomethylene)bisphosphonates using (MeO)2P(O)H/(MeO)3CH or (EtO)2P(O)H/(EtO)3CH reactant pairs and even secondary amines. Several intermediates referring to the reaction mechanism together with a few by-products could also be identified.

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Pyrene Carboxylate Ligand Based Coordination Polymers for Microwave-Assisted Solvent-Free Cyanosilylation of Aldehydes

Molecules ◽

10.3390/molecules26041101 ◽

2021 ◽

Vol 26 (4) ◽

pp. 1101

Author(s):

Anirban Karmakar ◽

Anup Paul ◽

Elia Pantanetti Sabatini ◽

M. Fátima C. Guedes da Silva ◽

Armando J. L. Pombeiro

Keyword(s):

Coordination Polymer ◽

Single Crystal ◽

Coordination Polymers ◽

Metal Ion ◽

Solvent Free ◽

Lewis Acidity ◽

Carboxylate Ligand ◽

X Ray Diffraction ◽

X Ray ◽

Microwave Assisted

The new coordination polymers (CPs) [Zn(μ-1κO1:1κO2-L)(H2O)2]n·n(H2O) (1) and [Cd(μ4-1κO1O2:2κN:3,4κO3-L)(H2O)]n·n(H2O) (2) are reported, being prepared by the solvothermal reactions of 5-{(pyren-4-ylmethyl)amino}isophthalic acid (H2L) with Zn(NO3)2.6H2O or Cd(NO3)2.4H2O, respectively. They were synthesized in a basic ethanolic medium or a DMF:H2O mixture, respectively. These compounds were characterized by single-crystal X-ray diffraction, FTIR spectroscopy, thermogravimetric and elemental analysis. The single-crystal X-ray diffraction analysis revealed that compound 1 is a one dimensional linear coordination polymer, whereas 2 presents a two dimensional network. In both compounds, the coordinating ligand (L2−) is twisted due to the rotation of the pyrene ring around the CH2-NH bond. In compound 1, the Zn(II) metal ion has a tetrahedral geometry, whereas, in 2, the dinuclear [Cd2(COO)2] moiety acts as a secondary building unit and the Cd(II) ion possesses a distorted octahedral geometry. Recently, several CPs have been explored for the cyanosilylation reaction under conventional conditions, but microwave-assisted cyanosilylation of aldehydes catalyzed by CPs has not yet been well studied. Thus, we have tested the solvent-free microwave-assisted cyanosilylation reactions of different aldehydes, with trimethylsilyl cyanide, using our synthesized compounds, which behave as highly active heterogeneous catalysts. The coordination polymer 1 is more effective than 2, conceivably due to the higher Lewis acidity of the Zn(II) than the Cd(II) center and to a higher accessibility of the metal centers in the former framework. We have also checked the heterogeneity and recyclability of these coordination polymers, showing that they remain active at least after four recyclings.

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Aminkomplexe des Goldes, Teil 9: Gold(I)-halogenid-Komplexe mit primären und azyklischen sekundären Aminen und ihre Oxidation zu Gold(III)-Derivaten

Zeitschrift für Naturforschung B ◽

10.1515/znb-2017-0182 ◽

2018 ◽

Vol 73 (1) ◽

pp. 43-74 ◽

Cited By ~ 3

Author(s):

Cindy Döring ◽

Peter G. Jones

Keyword(s):

Hydrogen Bonds ◽

Structure Analysis ◽

Secondary Amine ◽

Primary Amine ◽

Solvent Free ◽

Secondary Amines ◽

Primary Amines ◽

Direct Reaction ◽

X Ray

AbstractThe reaction of (tht)AuX (X=Cl or Br; tht=tetrahydrothiophene) with various primary amines L leads to products of the form [L2Au]+X−. Packing diagrams of the corresponding structures are dominated by N–H···X hydrogen bonds and (in some cases) aurophilic contacts. The cyclohexylamine derivative was already known as its dichloromethane ⅔-solvate; we have isolated the solvent-free compound and its pentane ¼-solvate, which all show different packing patterns. With acyclic secondary amines, the products are more varied; LAuX and [L2Au]+[AuX2]− were also found. These gold(I) products were generally formed in satisfactory quantities. The attempted oxidation to Au(III) derivatives with PhICl2 or Br2 proved impossible for the primary amine derivatives [although isopropylamine-trichloridogold(III) was obtained unexpectedly from the corresponding cyanide] and unsatisfactory for the secondary amine derivatives. Products LAuX3 and [L2AuX2]+[AuX4]− were identified but were formed in disappointing yields. In isolated cases protonated products (LH)+[AuCl4]−, (LH+)3[AuCl4]−(Cl−)2 or [(Et2N)2CH]+[AuBr4]− were formed, presumably by involvement of the dichloromethane solvent and/or adventitious water. Here also the yields were poor, and some products arose as mixtures. Direct reaction of amines with AuCl3 or (tht)AuX3 was also unsuccessful. All products were characterized by X-ray structure analysis.

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Continuous flow synthesis of α-aryl-α-aminophosphonates

Pure and Applied Chemistry ◽

10.1515/pac-2018-0923 ◽

2019 ◽

Vol 91 (1) ◽

pp. 67-76 ◽

Cited By ~ 6

Author(s):

Erika Bálint ◽

Ádám Tajti ◽

Katalin Ladányi-Pára ◽

Nóra Tóth ◽

Béla Mátravölgyi ◽

...

Keyword(s):

Continuous Flow ◽

Reaction Times ◽

Primary Amines ◽

Flow Process ◽

Flow Synthesis ◽

Microwave Reactor ◽

Dialkyl Phosphites ◽

Benzaldehyde Derivatives

AbstractThe synthesis of α-aryl-α-aminophosphonates was performed by the three-component Kabachnik-Fields reaction of primary amines, benzaldehyde derivatives and dialkyl phosphites in a continuous flow microwave reactor. The target compounds could be obtained in high (~90%) yields without any catalyst in simple alcohols as the solvent. The flow process elaborated required shorter reaction times and lower excess of the reagent, as compared to the “traditional” batch reactions, and allowed the synthesis of the α-aminophosphonates on a somewhat larger scale.

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To date the greenest method for the preparation of α-hydroxyphosphonates from substituted benzaldehydes and dialkyl phosphites

Green Processing and Synthesis ◽

10.1515/gps-2016-0125 ◽

2017 ◽

Vol 6 (2) ◽

Cited By ~ 3

Author(s):

György Keglevich ◽

Zita Rádai ◽

Nóra Zsuzsa Kiss

Keyword(s):

General Procedure ◽

Solvent Free ◽

Pure Form ◽

Synthetic Methods ◽

Green Solvent ◽

Minimum Quantity ◽

Pudovik Reaction ◽

Dialkyl Phosphites ◽

The Pudovik Reaction ◽

Substituted Benzaldehydes

AbstractRecent synthetic methods for α-hydroxyphosphonates comprise a green, solvent-free accomplishment of the Pudovik reaction that was typically followed by extractions and recrystallization, or even by chromatography, or other operations. We now developed a general procedure applying 10% of triethylamine as the catalyst and a minimum quantity of acetone as the solvent, giving the products in a pure form after a reflux of 5–120 min following the addition of some

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1D Zn(II) Coordination Polymers as Effective Heterogeneous Catalysts in Microwave-Assisted Single-Pot Deacetalization-Knoevenagel Tandem Reactions in Solvent-Free Conditions

Catalysts ◽

10.3390/catal11010090 ◽

2021 ◽

Vol 11 (1) ◽

pp. 90

Author(s):

Anup Paul ◽

Anirban Karmakar ◽

M. Fátima C. Guedes da Silva ◽

Armando J. L. Pombeiro

Keyword(s):

Carboxylic Acid ◽

Diffraction Analysis ◽

Heterogeneous Catalysts ◽

Topological Analysis ◽

Solvent Free ◽

Tandem Reactions ◽

X Ray Diffraction ◽

X Ray ◽

Microwave Assisted ◽

Solvent Free Conditions

The new 1D CPs [Zn(L1)(H2O)4]n.nH2O (1) and [Zn(L2)(H2O)2]n (2) [L1 = 1,1′-(ethane-1,2-diyl)bis(6-oxo-1,6-dihydropyridine-3-carboxylic acid); L2 = 1,1′-(propane-1,3-diyl)bis(6-oxo-1,6-dihydropyridine-3-carboxylic acid)] were prepared from flexible dicarboxylate pro-ligands (H2L1 and H2L2). Both CPs 1 and 2 were characterized by elemental, FTIR, and powder X-ray diffraction analysis. Their geometry and the structural features were unveiled by single-crystal X-ray diffraction analysis. The underlying topology of the CPs was illustrated by the topological analysis of the H-bonded structure of CP 1, which revealed a 3,4,6-connected trinodal net. On the other hand, topological analysis on the hydrogen-bonded network of CP 2 showed a 2,3,3,4,6,7-connected hexanodal net. The thermal stability of the CPs was investigated by thermogravimetric analysis. CPs 1 and 2 act as heterogeneous catalysts in one-pot tandem deacetalization–Knoevenagel condensation reactions under environmentally mild conditions. CPs 1 exhibits a yield of ca. 91% in a microwave-assisted solvent-free medium, whereas a slightly lower yield was obtained for CP 2 (87%) under the same experimental protocol. The recyclability of catalyst 1 was also assessed. To our knowledge, these are the first Zn(II)-based CPs to be applied as heterogeneous catalysts for the above tandem reactions under environmentally friendly conditions.

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The Addition of Dialkyl Phosphites and Diphenylphosphine Oxide on the Triple Bond of Dimethyl Acetylenedicarboxylate under Solvent-Free and Microwave Conditions

Current Organic Synthesis ◽

10.2174/1570179411999140304142747 ◽

2014 ◽

Vol 11 (1) ◽

pp. 161-166 ◽

Cited By ~ 11

Author(s):

Gyorgy Keglevich ◽

Erika Bálint ◽

Judit Takács ◽

László Drahos ◽

Krzysztof Huben ◽

...

Keyword(s):

Triple Bond ◽

Solvent Free ◽

Dimethyl Acetylenedicarboxylate ◽

Diphenylphosphine Oxide ◽

Dialkyl Phosphites

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Microwave-Assisted Kabachnik–Fields Reaction with Amino Alcohols as the Amine Component

Molecules ◽

10.3390/molecules24081640 ◽

2019 ◽

Vol 24 (8) ◽

pp. 1640 ◽

Cited By ~ 3

Author(s):

Tajti ◽

Szatmári ◽

Perdih ◽

Keglevich ◽

Bálint

Keyword(s):

Amino Alcohols ◽

Molar Ratio ◽

Secondary Phosphine ◽

Phosphine Oxides ◽

X Ray ◽

Microwave Assisted ◽

Dialkyl Phosphites ◽

By Products ◽

Hydroxyethyl Group ◽

Aminophosphine Oxide

In this paper, the microwave (MW)-assisted catalyst-free and mostly solvent-free Kabachnik–Fields reaction of amino alcohols, paraformaldehyde, and various >P(O)H reagents (dialkyl phosphites, ethyl phenyl-H-phosphinate, and secondary phosphine oxides) is reported. The synthesis of N-2-hydroxyethyl-αaminophosphonate derivatives was optimized in respect of the temperature, the reaction time, and the molar ratio of the starting materials. A few by-products were also identified. N,NBis(phosphinoylmethyl)amines containing a hydroxyethyl group were also prepared by the double Kabachnik–Fields reaction of ethanolamine with an excess of paraformaldehyde and secondary phosphine oxides. The crystal structure of a 2-hydroxyethyl-α-aminophosphine oxide and a bis(phosphinoylmethyl)ethanolamine was studied by X-ray analysis.

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Microwave Assisted Expeditious and Green Cu(II)-Clay Catalyzed Domino One-Pot Three Component Synthesis of 2H-indazoles

BULLETIN OF CHEMICAL REACTION ENGINEERING AND CATALYSIS ◽

10.9767/bcrec.13.1.963.82-88 ◽

2018 ◽

Vol 13 (1) ◽

pp. 82

Author(s):

Bashir Ahmad Dar ◽

Syed Wasim Safvi ◽

Masood Ahmad Rizvi

Keyword(s):

Reaction Engineering ◽

Primary Amines ◽

Efficient Synthesis ◽

X Ray Diffraction ◽

Title Reaction ◽

One Pot ◽

X Ray ◽

Microwave Assisted ◽

Clay Catalyst ◽

Scanning Electron

A simple and efficient synthesis of 2H-indazoles is achieved from 2-primary amines, bromobenzaldehydes and sodium azide through domino condensation, C–N and N–N bond formations, catalyzed by a heterogeneous Cu(II)-Clay catalyst. The recyclable heterogeneous Cu(II)-Clay catalyst exhibited a remarkable activity for the title reaction without any additives. An assortment of structurally diverse 2H-indazoles were prepared in good to excellent yields from easily available starting materials by using this protocol. The Cu(II)-Clay catalyst was characterized by using X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), and Brunauer-Emmett-Teller (BET) techniques. Copyright © 2018 BCREC Group. All rights reservedReceived: 24th February 2017; Revised: 8th August 2017; Accepted: 23rd August 2017; Available online: 22nd January 2018; Published regularly: 2nd April 2018How to Cite: Dar, B.A., Safvi, S.W., Rizvi, M.A. (2018). Microwave Assisted Expeditious and Green Cu(II)-Clay Catalyzed Domino One-Pot Three Component Synthesis of 2H-indazoles. Bulletin of Chemical Reaction Engineering & Catalysis, 13 (1): 82-88 (doi:10.9767/bcrec.13.1.963.82-88)

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