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

Molecules ◽  
2019 ◽  
Vol 24 (8) ◽  
pp. 1640 ◽  
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.

Microwave-assisted alcoholysis of dialkyl phosphites by ethylene glycol and ethanolamine

2014 ◽  
Vol 86 (11) ◽  
pp. 1723-1728 ◽  
Author(s):  
György Keglevich ◽  
Erika Bálint ◽  
Ádám Tajti ◽  
Béla Mátravölgyi ◽  
György Tibor Balogh ◽  
...  
Keyword(s):  
Ethylene Glycol ◽  
Alkyl Substituent ◽  
Molar Ratio ◽  
Diethyl Phosphite ◽  
Microwave Assisted ◽  
Dialkyl Phosphites ◽  
By Products

Abstract A study on the microwave-assisted alcoholysis of diethyl phosphite with ethylene glycol revealed that after optimization of the conditions (molar ratio, temperature and time), the target “monomer,” (HOCH2CH2O)2P(O)H was formed in a proportion of 59 %, but with an incomplete conversion. The formation of the (HOCH2CH2O)(EtO)P(O)H and H(EtO)(O)POCH2CH2OP(O)(OEt)H by-products was, in most cases, inevitable. The alcoholysis with ethanolamine was more efficient and took place in a conversion of 100 % to afford H2NCH2CH2O)2P(O)H in a proportion of 85 %. An alkyl substituent on the N-atom prevented the alcoholysis.

Microwave-Assisted Solution Combustion Synthesis and Characterization of Thermoelectric Ca3Co2O6 Powders

2013 ◽  
Vol 802 ◽  
pp. 84-88
Author(s):  
Sagulthai Kahatta ◽  
Nopsiri Chaiyo ◽  
Chesta Ruttanapun ◽  
Wicharn Techitdheera ◽  
Wisanu Pecharapa ◽  
...  
Keyword(s):  
Combustion Synthesis ◽  
Solution Combustion Synthesis ◽  
Molar Ratio ◽  
X Ray Diffraction ◽  
Solution Combustion ◽  
X Ray ◽  
Microwave Assisted ◽  
Product Characterization ◽  
Rhombohedral Crystal Structure ◽  
Rhombohedral Crystal

The microwave-assisted solution combustion synthesis was applied to the initial synthesizing of Ca3Co2O6powder using glycine as a fuel and nitrate as an oxidant. The as-synthesized powders were calcined at 700-1,000ºC for 4h. Product characterization was performed using Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD) and Scanning electron microscope (SEM). The fuel-to-oxidizer molar ratio was found to affect the combustion reaction and character of the powder obtained. The phase composition of powder after calcination at various temperatures has shown that the formation of Ca3Co2O6occurs directly. The calcined powder possesses a rhombohedral crystal structure with an X-ray diffraction pattern that could be matched with the Ca3Co2O6JCPDS: 89-0629. This method is a simple way of synthesizing fine Ca3Co2O6powder with a low calcination temperature.

Synthesis of Fe2O3/C Nanocomposite Using Microwave Assisted Calcination Method

2014 ◽  
Vol 896 ◽  
pp. 100-103 ◽  
Author(s):  
Anggi Puspita Swardhani ◽  
Ferry Iskandar ◽  
Abdullah Mikrajuddin ◽  
Khairurrijal
Keyword(s):  
Crystallite Size ◽  
Average Particle Size ◽  
Molar Ratio ◽  
Average Particle ◽  
X Ray ◽  
Molar Ratios ◽  
Microwave Assisted ◽  
Chloride Hexahydrate ◽  
Calcination Method ◽  
Scherrer Method

Fe2O3/C nanocomposites were successfully synthesized using microwave assisted calcination method. Ferric (III) chloride hexahydrate (FeCl36H2O), sodium hydroxide (NaOH), and dextrose monohydrate (C6H12O6H2O) were used as precursors. A microwave oven of 2.445 GHz with a power of 600 W for 20 minutes was employed during the syntheses. Calcination was performed in a simple furnace at 350 °C for 30 min. The molar ratio of C:Fe is the only process parameter. From Scanning Electron Microscope images, the average particle size were 199 nm and 74 nm for the samples with molar ratio of C:Fe of 1:2 and 1:1, respectively. X-ray diffractometer spectra showed that the obtained samples have γ-Fe2O3 (maghemite) crystal structure. Using the Scherrer method, the crystallite size were 61.7, 58.8, 52.5, and 48.8 nm for the samples with the molar ratios of C:Fe of 1:3, 1:2, 1:1, and 2:1, respectively. It means that the crystallite size of the nanocomposite decreases with the increase of the molar ratio of carbon to iron (C:Fe). The Brunauer-Emmett-Teller characterization showed that the surface area as high as 255.6 m2/g is achieved by of the Fe2O3/C nanocomposite with the molar ratio of C:Fe of 1:1.

Organophosphorverbindungen mit tertiären Alkylsubstituenten. III*: Synthese und Reaktionen Di-1-adamantylsubstituierter Phosphorverbindungen; Kristallstruktur von Di-1-Adamantylphosphinsäurechlorid / Organophosphorus Compounds with Tertiary Alkyl Substituents. Ill: Synthesis and Reactions of Di-1-adam antyl-Substituted Phosphorus Compounds; Crystal Structure of Di-1-adam antylphosphinic Chloride

1994 ◽  
Vol 49 (6) ◽  
pp. 801-811 ◽  
Author(s):  
Jens R. Goerlich ◽  
Axel Fischer ◽  
Peter G. Jones ◽  
Reinhard Schmutzler
Keyword(s):  
Organophosphorus Compounds ◽  
Phosphorus Compounds ◽  
Secondary Phosphine ◽  
Phosphine Oxides ◽  
X Ray ◽  
Dry Air ◽  
Nmr Data ◽  
Standard Procedures ◽  
Hydrolysis Of ◽  
Tertiary Alkyl

The reaction of adamantane with PCl3/A1Cl3, followed by hydrolysis, gave (1-Ad)2P(:O)Cl 1, which was converted to (1-Ad)2P(:O)F 2 and (1-Ad)2P(:S)Cl 3 by standard procedures. The structure of 1 was confirmed by a single crystal X-ray structure determination; despite the bulky substituents the P-C bond lengths are normal (184.0(3), 185.0(3) pm). Whereas chlorine-fluorine exchange in 3 with AsF3 furnished (1-Ad)2P(:S)F 4, desulfuration of 3 with Ph3P to give (1-Ad)2PCl 5 failed. The secondary phosphine oxides R 1R2P(:O)H (R1, R2 = 1-Ad: 6; R1 = 1-Ad, R2 = tBu: 7; R1, R2 = tBu: 8) were synthesized by reaction of 1, 1-AdP(:O)Cl2 and tBuP(:0)Cl2 with tBuLi. 6 and 8 reacted readily with chloral to give the adducts R2P(:O)CH(OH)CCl3 (R = 1-Ad: 9; R = tBu: 10). Silylation of 6 with Me2NSiMe3 in the presence of dry air led to (1-Ad)2P(:O)OSiMe3 11, which was hydrolyzed to give (1-Ad)2P(:O)OH 12. (1-Ad)2POSiMe3 13 was obtained by the reaction of 6 with n-BuLi, followed by Me3SiCl. No reaction took place upon heating 6 with Mo(CO)6. (1-Ad)2PCl 5 was synthesized in low yield by the reaction of 6 with PCl3. The action of tetrachloro-obenzoquinone (TOB) upon 6 furnished (1-Ad)2P(:O)(o-OH)C6Cl4 15, whereas the tbutyl analogue of 15, 16, was synthesized by hydrolysis of the TOB-adduct of di-tbutylfluorophosphine. Analogous 1-adamantyl- and tbutyl-phosphorus compounds are compared with regard to their 31P NMR data

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

2017 ◽  
Vol 13 ◽  
pp. 76-86 ◽  
Author(s):  
Erika Bálint ◽  
Ádám Tajti ◽  
Anna Ádám ◽  
István Csontos ◽  
Konstantin Karaghiosoff ◽  
...  
Keyword(s):  
Dft Calculations ◽  
Solvent Free ◽  
Primary Amines ◽  
Diphenylphosphine Oxide ◽  
Dimer Formation ◽  
X Ray ◽  
Microwave Assisted ◽  
Pudovik Reaction ◽  
Dialkyl Phosphites ◽  
Benzaldehyde Derivatives

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.

scholarly journals Production of Triacetin by Microwave Assisted Esterification of Glycerol Using Activated Natural Zeolite

2019 ◽  
Vol 14 (3) ◽  
pp. 672 ◽  
Author(s):  
Marwan Marwan ◽  
Eti Indarti ◽  
Darmadi Darmadi ◽  
Wahyu Rinaldi ◽  
Dzikri Hamzah ◽  
...  
Keyword(s):  
Natural Zeolite ◽  
Xrd Analysis ◽  
Molar Ratio ◽  
Catalyst Loading ◽  
X Ray Diffraction ◽  
X Ray ◽  
Microwave Assisted ◽  
Infra Red ◽  
Sem Micrograph ◽  
The Fourier Transform

Triacetin, an alternative biodiesel additive, was prepared by esterification of glycerol with acetic acid in the presence of chemically activated natural zeolite. The esterification was carried out in a small reaction flask under microwave irradiation. The catalyst was characterized for its morphology by SEM and its chemical composition by X-ray Diffraction (XRD). The Scanning Electron Microscopy (SEM) micrograph indicates improved surface area of the zeolite, while the XRD analysis shows an increase in Si/Al ratio from natural zeolite to 6.042 and its crystallinity value of 12.23%. The Fourier Transform Infra Red (FTIR) analysis obtained showed that microwave-heated samples have an esters group spectrum of triacetin at 1702 cm-1. The conversion value of glycerol was more than 95% at molar ratio of the reactants 1:9 and catalyst loading of 3%. The selectivities for monoacetin, diacetin and triacetin were 80.1%, 15.4%, and 4.5% at 60 minutes, and 43.0%, 48.6%, and 8.3% at 90 minutes. It shows that the conversion took place in consecutive steps and the use of microwave allows the reaction proceeding at milder condition. Copyright © 2019 BCREC Group. All rights reserved 

scholarly journals Oyster andPyramidellaShells as Heterogeneous Catalysts for the Microwave-Assisted Biodiesel Production fromJatropha curcasOil

2015 ◽  
Vol 2015 ◽  
pp. 1-7 ◽  
Author(s):  
Achanai Buasri ◽  
Tidarat Rattanapan ◽  
Chalida Boonrin ◽  
Chosita Wechayan ◽  
Vorrada Loryuenyong
Keyword(s):  
Jatropha Curcas ◽  
Heterogeneous Catalysts ◽  
Biodiesel Production ◽  
Bet Surface Area ◽  
Molar Ratio ◽  
Catalyst Loading ◽  
X Ray ◽  
Microwave Assisted ◽  
Xrf Scanning ◽  
Waste Shell

Microwave-assisted biodiesel production via transesterification ofJatropha curcasoil with methanol using solid oxide catalyst derived from waste shells of oyster andPyramidellawas studied. The shells were calcined at 900°C for 2 h and calcium oxide (CaO) catalyst characterizations were carried out by X-ray diffraction (XRD), X-ray fluorescence (XRF), scanning electron microscope (SEM), and the Brunauer-Emmett-Teller (BET) surface area measurements. The effects of reaction variables such as reaction time, microwave power, methanol/oil molar ratio, and catalyst loading on the yield of biodiesel were investigated. Reusability of waste shell catalyst was also examined. The results indicated that the economic and environmentally friendly catalysts derived from oyster andPyramidellashells showed good reusability and had high potential to be used as biodiesel production catalysts under microwave-assisted transesterification ofJatropha curcasoil with methanol.

ChemInform Abstract: P-Arylation of Dialkyl Phosphites and Secondary Phosphine Oxides with Arynes.

ChemInform ◽  
2016 ◽  
Vol 47 (20) ◽  
Author(s):  
Qian Chen ◽  
Xinxing Yan ◽  
Zhiyun Du ◽  
Kun Zhang ◽  
Chunxiao Wen
Keyword(s):  
Secondary Phosphine ◽  
Phosphine Oxides ◽  
Dialkyl Phosphites

scholarly journals Asymmetric Synthesis of the Two Enantiomers of β-Phosphorus-containing α-Amino Acids via Hydrophosphinylation and Hydrophosphonylation of Chiral Ni(II)-Complexes

2021 ◽  
Author(s):  
Isabelle Gillaizeau ◽  
Yoshinori Tokairin ◽  
Hiroyuki Konno ◽  
Angéline Noireau ◽  
Caroline West ◽  
...  
Keyword(s):  
Amino Acids ◽  
Asymmetric Synthesis ◽  
Michael Addition ◽  
Secondary Phosphine ◽  
Phosphine Oxides ◽  
New Approach ◽  
Phosphorus Containing ◽  
Dialkyl Phosphites

A new approach for the asymmetric synthesis of the two enantiomers of β-phosphorus-containing α-amino acids was developed via Michael addition of secondary phosphine oxides and dialkyl phosphites to chiral Ni...

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