Continuous flow photolysis of aryl azides: Preparation of 3H-azepinones

Photolysis of aryl azides to give nitrenes, and their subsequent rearrangement in the presence of water to give 3H-azepinones, is performed in continuous flow in a photoreactor constructed of fluorinated ethylene polymer (FEP) tubing. Fine tuning of the reaction conditions using the flow reactor allowed minimization of secondary photochemical reactions.

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Nanocrystals Synthesis by Microreactors

Advances in Science and Technology ◽

10.4028/www.scientific.net/ast.45.652 ◽

2006 ◽

Vol 45 ◽

pp. 652-659

Author(s):

Hiroyuki Nakamura ◽

Masato Uehara ◽

Hideaki Maeda

Keyword(s):

Particle Size ◽

Optical Properties ◽

Continuous Flow ◽

Flow Reactor ◽

Reaction Conditions ◽

Control Reaction ◽

Continuous Flow Reactor

A microreactor is a continuous flow reactor, which can control reaction conditions precisely. We applied the microreactors to CdSe based nanocrystals synthesis and tuning particle size, optical properties. Furthermore, homogeneous coating of ZnS and its coating amount tuning was possible for optical properties improvement.

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Continuous Flow Friedel–Crafts Alkylation Catalyzed by Silica Supported Phosphotungstic Acid: An Environmentally Benign Process

Topics in Catalysis ◽

10.1007/s11244-021-01497-y ◽

2021 ◽

Author(s):

Zsófia Császár ◽

Tatjána Juzsakova ◽

Miklós Jakab ◽

Szabolcs Balogh ◽

Ágnes Szegedi ◽

...

Keyword(s):

Flow Rate ◽

Continuous Flow ◽

Phosphotungstic Acid ◽

Flow Reactor ◽

Analytical Techniques ◽

Catalyst System ◽

Molar Ratio ◽

Flow Mode ◽

Reaction Conditions ◽

Composite Catalysts

AbstractSix silica-supported phosphotungstic acid catalysts (PTA/SiO2) of different composition (20–70 wt% PTA content) have been synthesized and characterized by elemental analysis, BET, BJH, NH3-TPD methods, FT-IR spectroscopy of adsorbed pyridine and 1H MAS NMR techniques. The new composite catalysts were first applied in the Friedel–Crafts alkylation of toluene with 1-octene as a benchmark process under batch conditions in order to screen their activity and recyclability. The combined analytical techniques together with the catalytic studies enabled the identification of the main factors affecting the activity of the catalysts. Based on these preliminary experiments, the best performing catalyst system (50 wt% PTA/SiO2) was investigated in continuous flow mode using an in-house-made flow reactor. The thorough screening of the reaction conditions (temperature, toluene/1-octene molar ratio and flow rate) provided firm evidence that the 50 wt% PTA/SiO2 composite is highly active, selective and stable catalyst under mild reaction conditions even at elevated flow rate. Additionally, the catalyst used in the flow mode could successfully be regenerated and reused in the alkylation process.

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The development and evaluation of a continuous flow process for the lipase-mediated oxidation of alkenes

Beilstein Journal of Organic Chemistry ◽

10.3762/bjoc.5.27 ◽

2009 ◽

Vol 5 ◽

Cited By ~ 35

Author(s):

Charlotte Wiles ◽

Marcus J Hammond ◽

Paul Watts

Keyword(s):

Continuous Flow ◽

Flow Reactor ◽

Preliminary Investigation ◽

Enzymatic Oxidation ◽

High Yield ◽

Reaction Conditions ◽

Flow Process ◽

Continuous Flow Reactor ◽

Yield And Purity ◽

Mediated Oxidation

We report the use of an immobilised form of Candida antarctica lipase B, Novozym® 435, in a preliminary investigation into the development of a continuous flow reactor capable of performing the chemo-enzymatic oxidation of alkenes in high yield and purity, utilising the commercially available oxidant hydrogen peroxide (100 volumes). Initial investigations focussed on the lipase-mediated oxidation of 1-methylcyclohexene, with the optimised reaction conditions subsequently employed for the epoxidation of an array of aromatic and aliphatic alkenes in 97.6 to 99.5% yield and quantitative purity.

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Photochemical intramolecular amination for the synthesis of heterocycles

Green Chemistry ◽

10.1039/c7gc02261a ◽

2017 ◽

Vol 19 (20) ◽

pp. 4798-4803 ◽

Cited By ~ 22

Author(s):

Shawn Parisien-Collette ◽

Corentin Cruché ◽

Xavier Abel-Snape ◽

Shawn K. Collins

Keyword(s):

Continuous Flow ◽

Flow Reactor ◽

Aryl Azides ◽

Photochemical Conversion ◽

Continuous Flow Reactor

Polycyclic heterocycles can be formed in good to excellent yields via photochemical conversion of the corresponding substituted aryl azides under irradiation with purple LEDs in a continuous flow reactor.

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Renewable Energy from Agricultural Waste

Revista de Chimie ◽

10.37358/rc.18.6.6325 ◽

2018 ◽

Vol 69 (6) ◽

pp. 1363-1366 ◽

Cited By ~ 1

Author(s):

Stefania Daniela Bran ◽

Petre Chipurici ◽

Mariana Bran ◽

Alexandru Vlaicu

Keyword(s):

Saccharomyces Cerevisiae ◽

Gas Chromatography ◽

Continuous Flow ◽

Laboratory Experiments ◽

Fermentation Process ◽

Flow Reactor ◽

Agricultural Waste ◽

Continuous Flow Reactor ◽

Natural Support ◽

Co2 Flow

This paper has aimed at evaluating the concentration of bioethanol obtained using sunflower stem as natural support, molasses as carbon source and Saccharomyces cerevisiae yeast in a continuous flow reactor. The natural support was tested to investigate the immobilization/growth of S. cerevisiae yeast. The concentration of bioethanol produced by fermentation was analyzed by gas chromatography using two methods: aqueous solutions and extraction in organic phase. The CO2 flow obtained during the fermentation process was considered to estimate when the yeast was deactivated. The laboratory experiments have highlighted that the use of plant-based wastes to bioconversion in ethanol could be a non-pollutant and sustainable alternative.

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Synthesis of Phosphonates via Michaelis-Arbuzov Reaction

Current Organic Synthesis ◽

10.2174/1570179414666161230144455 ◽

2017 ◽

Vol 14 (6) ◽

pp. 883-903 ◽

Cited By ~ 4

Author(s):

Boppudi Hari Babu ◽

Gandavaram Syam Prasad ◽

Chamarthi Naga Raju ◽

Mandava Venkata Basaveswara Rao

Keyword(s):

Reaction Times ◽

Biologically Active ◽

Fine Tuning ◽

Arbuzov Reaction ◽

Reaction Conditions ◽

Solvent Type ◽

Potential Applications ◽

Synthetic Methodologies ◽

Optimal Reaction ◽

The Arbuzov Reaction

Background: Michaelis–Arbuzov reaction has played a key role for the synthesis of dialkyl or diaryl phosphonates by reacting various alkyl or aryl halides with trialkyl or triaryl phosphite. This reaction is very versatile in the formation of P-C bond from the reaction of aliphatic halides with phosphinites or phosphites to yield phosphonates, phosphinates, phosphine oxides. The Arbuzov reaction developed some methodologies, possible mechanistic pathways, selectivity, potential applications and biologically active various phosphonates. Objective: The synthesis of phosphonates via Michaelis–Arbuzov reaction with many new and fascinating methodologies were developed and disclosed in the literature, and these are explored in this review. Conclusion: This review has discussed past developments and vast potential applications of Arbuzov reaction in the synthesis of organophosphonates. As presented in this review, various synthetic methodologies were developed to prepare a large variety of phosphonates. Improvements in the reaction conditions of Lewis-acid mediated Arbuzov rearrangement as well as the development of MW-assisted Arbuzov rearrangement were discussed. Finally, to achieve high selectivities and yields, fine-tuning of reaction conditions including solvent type, temperature, and optimal reaction times to be considered.

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