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Search for "flow chemistry" in Full Text gives 128 result(s) in Beilstein Journal of Organic Chemistry.
Microfluidic light-driven synthesis of tetracyclic molecular architectures
Beilstein J. Org. Chem. 2018, 14, 2418–2424, doi:10.3762/bjoc.14.219
- molecules. Keywords: [4 + 2] photoenol; cycloaddition; flow chemistry; microfluidic photoreactor; photoredox catalysis; synthetic photochemistry; Introduction In recent years synthetic photochemistry has become highly sophisticated [1]. The opportunity of using renewable energy sources to transform and
Applications of organocatalysed visible-light photoredox reactions for medicinal chemistry
Beilstein J. Org. Chem. 2018, 14, 2035–2064, doi:10.3762/bjoc.14.179
- reaction specifically investigated the dimerization of thiols. Some of the experiments carried out by the group were in a flow chemistry set up, exemplifying the scalability of the procedure. In addition, the oxidant that achieves the transformation is molecular oxygen, making this a very sustainable route
- an organophotocatalytic version of the Ugi reaction. These procedures were undertaken in a flow chemistry set-up, using irradiation by green LEDs and Rose Bengal as the photocatalyst (Scheme 13) [56]. The scope of the reaction is fairly broad, especially considering the method was developed in a flow
- chemistry set-up, which requires a large amount of optimisation itself. A range of nucleophiles including nitroalkanes, cyanides, malonates and phosphonates are used to modify different N-aryltetrahydroisoquinolines. These products have the potential for quite a range of subsequent reactions for elaboration
Assessing the possibilities of designing a unified multistep continuous flow synthesis platform
Beilstein J. Org. Chem. 2018, 14, 1917–1936, doi:10.3762/bjoc.14.166
- ’, in reality, such an envisaged system would be much more complex than these examples. Keywords: automation; continuous flow synthesis; cybernetics; multistep flow synthesis; unified platforms; Review Introduction Flow chemistry is now seen as a reliable approach for the synthesis of simple organic
- ]. Flow chemistry gains its benefits from excellent heat and mass transfer rates and rapid mixing which is not possible in the case of conventional synthesis modes [21]. In general, the continuous flow synthesis aims at conducting the reactions at intrinsic kinetics. This helps to have reactors having
- of flow chemistry which is not an easy task. The utilization of the same approach for the synthesis of a wide range of products is very challenging since each product in the chemical synthesis involves different synthesis procedures, different conditions, different phases and different isolation
Mild and selective reduction of aldehydes utilising sodium dithionite under flow conditions
Beilstein J. Org. Chem. 2018, 14, 1529–1536, doi:10.3762/bjoc.14.129
- the selective reduction of aldehydes in the presence of ketones and has been demonstrated as a continuous process. Keywords: aldehyde reduction; flow chemistry; selective reduction; sodium dithionite; Introduction Flow chemistry and continuous processing has been acknowledged by the American
- Chemical Society (ACS), the Green Chemistry Institute (GCI) and several global pharmaceutical companies as one of the primary areas for research and development for chemical manufacturing [1][2][3][4]. For the past decade flow chemistry and the application of flow devices has been gaining acceptance in
Biocatalytic synthesis of the Green Note trans-2-hexenal in a continuous-flow microreactor
Beilstein J. Org. Chem. 2018, 14, 697–703, doi:10.3762/bjoc.14.58
- Engineering and Chemistry, Micro Flow Chemistry & Process Technology, Eindhoven University of Technology, Den Dolech 2, 5612 AZ Eindhoven, The Netherlands Centro de Investigaciones Biológicas, CSIC, Madrid, Spain 10.3762/bjoc.14.58 Abstract The biocatalytic preparation of trans-hex-2-enal from trans-hex-2
- ; alcohol oxidation; aldehyde; flow chemistry; Introduction trans-2-Hexenal is well-known as a major component of the Green Notes of fruits and vegetables such as apples, strawberries, cherries and more. It is widely used in the flavour and fragrance industry as fresh flavour ingredient in foods and
- induced by the segmented flow regime. This flow pattern guarantees an enhanced contact between the two phases and provides a uniform gas concentration in the liquid segment. Therefore, it is not very astonishing that also the biocatalysis community is showing interest in flow chemistry. Several
Heterogeneous Pd catalysts as emulsifiers in Pickering emulsions for integrated multistep synthesis in flow chemistry
Beilstein J. Org. Chem. 2018, 14, 648–658, doi:10.3762/bjoc.14.52
- . Keywords: compartmentalisation; heterogeneous catalysis; multistep flow chemistry; palladium; Pickering emulsions; Introduction Palladium (Pd) catalysis has been established as a key component in the toolbox of organic chemists. Reactions that are catalysed by palladium benefit from the remarkable
High-yielding continuous-flow synthesis of antimalarial drug hydroxychloroquine
Beilstein J. Org. Chem. 2018, 14, 583–592, doi:10.3762/bjoc.14.45
- starting materials and reagents, simplifying the synthetic route in terms of reducing the total number of steps as well as reducing the cost and improving the efficiency of individual steps. Flow chemistry methodologies have been increasingly investigated in recent years in the pharmaceutical industry for
- batch processes. HCQ (1) is currently produced via the batch method shown in Scheme 1. Therefore, continuous-flow chemistry approaches to synthesizing HCQ (1) offer a great potential to maximize the efficiency, and thus significantly reduces the overall manufacturing costs of this important medicine
- to limited solubility of ammonia in THF. H2/Raney-nickel reductions are often carried out in alcoholic media where much higher concentrations of ammonia are achievable but would require a solvent exchange. There are many reports of continuous-flow chemistry methods for reductive amination of ketones
Continuous multistep synthesis of 2-(azidomethyl)oxazoles
Beilstein J. Org. Chem. 2018, 14, 506–514, doi:10.3762/bjoc.14.36
- with unstable intermediates or reagents can be overcome with the use of continuous-flow chemistry. Continuous-flow processing has demonstrated to be an ideal tool for the development of uninterrupted multistep reactions [35][36][37]. The integration of several sequential steps can be readily achieved
Continuous-flow retro-Diels–Alder reaction: an efficient method for the preparation of pyrimidinone derivatives
Beilstein J. Org. Chem. 2018, 14, 318–324, doi:10.3762/bjoc.14.20
- , determining the reaction rate and the conversion and by influencing product selectivities [17][18][19]. Thus, flow chemistry has long been selected to provide a simple means to use more rigorous reaction conditions and revisit difficult reactions that have been neglected in the past [21]. The retro-Diels
- (DCB)], and under microwave (MW) conditions in DCB. In order to provide a rapid and efficient access to the desired pyrimidinones 9–14 (Scheme 1), we reinvestigated these rDA reactions by using another method involving flow chemistry. Therefore, a modular flow system was designed, equipped with a
- degradation of the rDA product. The conversion and yield of a reaction under CF conditions is influenced directly by the residence time and reaction temperature, which are crucial determining factors in flow chemistry [18][19][20]. Thus, these two parameters were fine-tuned for all of the starting materials
Progress in copper-catalyzed trifluoromethylation
Beilstein J. Org. Chem. 2018, 14, 155–181, doi:10.3762/bjoc.14.11
- as the CF3 source (Scheme 7). High temperature was required to accelerate the rate of the decarboxylation of CF3CO2K and the increased pressure occurred during the process, which brought problems under batch conditions. Buchwald and co-worker deal with it through combining flow chemistry. Under flow
A concise flow synthesis of indole-3-carboxylic ester and its derivatisation to an auxin mimic
Beilstein J. Org. Chem. 2017, 13, 2549–2560, doi:10.3762/bjoc.13.251
- also deemed highly desirable to be able to produce material on demand using a flexible scale flow chemistry approach. Since the report of the first synthetic access to indoles by Fischer in 1835 more than a dozen further unique indole syntheses have been reported showcasing the importance of developing
- were recorded on an automated melting point system with a heating rate of 1 °C/min and are uncorrected. Microwave optimisation reactions were performed in a Biotage® Initiator+ microwave system. Flow reactions were preformed using the pumping system of a Vapourtec R-Series modular flow chemistry system
- herbicide which was required for preliminary field trials. The overall synthetic approach and optimisation studies are described along with a full description of the final reactor configurations employed for the synthesis as well as the downstream processing of the reaction streams. Keywords: flow
Photocatalyzed synthesis of isochromanones and isobenzofuranones under batch and flow conditions
Beilstein J. Org. Chem. 2017, 13, 1456–1462, doi:10.3762/bjoc.13.143
- , when 2-vinylbenzoic acid derivatives were employed as reagents, isobenzofuranones were obtained together with unprecedented benzo[e][1,3]oxazepin-1(5H)-ones, with the latter derived from incorporation of the solvent (acetonitrile). Keywords: flow chemistry; heterocycles; multicomponent reactions
- decomposed during 13C NMR analysis). The interest of both academia and industry in flow chemistry has recently increased. In particular, photochemical reactions performed under continuous flow have been proven particularly effective [6], as the reduced size of the reaction channels allows for a more
Biomimetic molecular design tools that learn, evolve, and adapt
Beilstein J. Org. Chem. 2017, 13, 1288–1302, doi:10.3762/bjoc.13.125
- materials synthesis, characterization, and testing technologies – e.g., RAMP, flow chemistry, high-throughput beam lines, combinatorial chemistry. They suggest that an automatic, closed loop system could be developed where the fittest materials synthesized in a given generation are used to design the next
Automating multistep flow synthesis: approach and challenges in integrating chemistry, machines and logic
Beilstein J. Org. Chem. 2017, 13, 960–987, doi:10.3762/bjoc.13.97
- scale of operation. This classification will cover the broader range in the multistep synthesis literature. Keywords: automation; control strategy; flow chemistry; in-line monitoring; multistep synthesis optimization; Introduction Multistep flow synthesis In the recent time the concept of flow
- provide solutions for scale-up of lab processes [61][62][63][64][65][66][67] usually their hands-on experience to decide the control strategy while automating a flow chemistry always offers better solutions than what one expects theoretically. Before analysing these complex syntheses, it is worth
- chemistry has become an important milestone in organic and materials synthesis. It has also been proven to be successful for a large number of reactions and the natural evolution of flow synthesis was to extend for its applicability to complex chemistries and large molecules [1][2][3][4]. In general, the
Continuous-flow processes for the catalytic partial hydrogenation reaction of alkynes
Beilstein J. Org. Chem. 2017, 13, 734–754, doi:10.3762/bjoc.13.73
- process, aimed at illustrating the state of the art in the field and the benefits of the approach. Generalities on theory and methods for flow chemistry can be found in excellent textbooks and reviews [40][41] and will not be treated in detail. The present review could have been structured according to
Contribution of microreactor technology and flow chemistry to the development of green and sustainable synthesis
Beilstein J. Org. Chem. 2017, 13, 520–542, doi:10.3762/bjoc.13.51
- Flavio Fanelli Giovanna Parisi Leonardo Degennaro Renzo Luisi Department of Pharmacy – Drug Sciences, University of Bari “A. Moro”, FLAME-Lab – Flow Chemistry and Microreactor Technology Laboratory, Via E. Orabona 4, 70125, Bari. Italy 10.3762/bjoc.13.51 Abstract Microreactor technology and flow
- chemistry could play an important role in the development of green and sustainable synthetic processes. In this review, some recent relevant examples in the field of flash chemistry, catalysis, hazardous chemistry and continuous flow processing are described. Selected examples highlight the role that flow
- chemistry could play in the near future for a sustainable development. Keywords: flash chemistry; flow chemistry; green chemistry; microreactor technology; sustainable synthesis; Introduction Green chemistry’s birth was driven by the necessity to consider and face the urgent question of sustainability
A chemoselective and continuous synthesis of m-sulfamoylbenzamide analogues
Beilstein J. Org. Chem. 2017, 13, 303–312, doi:10.3762/bjoc.13.33
- , 15 analogues were synthesized, using similar conditions, with yields ranging between 65 and 99%. This is the first automated and chemoselective synthesis of m-sulfamoylbenzamide analogues. Keywords: flow chemistry; medium-throughput synthesis; m-sulfamoylbenzamide analogues; Introduction Small
- suitable hit is identified on the other hand, the synthetic prerequisites change completely, and a robust and scalable protocol is needed. Over the past few years, flow chemistry has emerged as a potential solution to these conflicting prerequisites [3][4][5][6][7][8][9][10][11]. Flow processing is
- unusual for flow chemistry. Typical batch reactions are mixed by stirring; however, perfect homogeneity is not immediately obtained. Ideal mixing conditions can only be achieved with microreactors or micromixers [22]. The small diameters of these microreactors lead to almost ideal mixing conditions [23
NMR reaction monitoring in flow synthesis
Beilstein J. Org. Chem. 2017, 13, 285–300, doi:10.3762/bjoc.13.31
- 10.3762/bjoc.13.31 Abstract Recent advances in the use of flow chemistry with in-line and on-line analysis by NMR are presented. The use of macro- and microreactors, coupled with standard and custom made NMR probes involving microcoils, incorporated into high resolution and benchtop NMR instruments is
- optimization is discussed. Keywords: expert systems; flow chemistry; microcoil; NMR probes; Introduction New enabling technologies have facilitated the transition from traditional chemistry to a more automated approach that will be the chemistry of the 21st century [1][2]. The objective is that the reaction
- planning, interpreting results and developing new projects. In this regard, flow chemistry is the central motif of this automated approach. In contrast to batch mode, in flow chemistry the starting materials are continuously introduced into the flow reactor (e.g., a microreactor or a column) and the
Continuous-flow synthesis of highly functionalized imidazo-oxadiazoles facilitated by microfluidic extraction
Beilstein J. Org. Chem. 2017, 13, 239–246, doi:10.3762/bjoc.13.26
- been used successfully in some cases [1][2][3][4][5][6]. However, this approach has a number of drawbacks, primarily because of mutual interference between various reactive components. Recently, continuous-flow chemistry has emerged as a powerful technique in organic synthesis. This is in part due to
- the potential for integrating individual reaction steps and subsequent separations into a single streamlined process [7][8][9][10][11][12][13][14]. On the other hand, a significant challenge in flow chemistry is the formation of insoluble intermediates in the reactor. This can often be prevented by
- describe the utilization of liquid–liquid microextraction to facilitate a complex, multistep flow synthesis process. Our research in the field of flow synthesis has focused on developing continuous-flow chemistry methods to access complex, drug-like molecules from readily available precursors without
Self-optimisation and model-based design of experiments for developing a C–H activation flow process
Beilstein J. Org. Chem. 2017, 13, 150–163, doi:10.3762/bjoc.13.18
- ; flow chemistry; process modelling; self-optimisation; Introduction The development of manufacturing processes to produce functional molecules, such as pharmaceuticals or fine chemicals, often relies on experience and trial-and-error, rather than on mechanistic process models [1]. The only reason for
Diels–Alder reactions of myrcene using intensified continuous-flow reactors
Beilstein J. Org. Chem. 2017, 13, 120–126, doi:10.3762/bjoc.13.15
- continuous-flow approach provides a facile alternative scale-up route to conventional batch processing, and it helps to intensify the synthesis protocol by applying higher reaction temperatures and shorter reaction times. Keywords: continuous processing; flow chemistry; renewable feedstock; surfactant
3D printed fluidics with embedded analytic functionality for automated reaction optimisation
Beilstein J. Org. Chem. 2017, 13, 111–119, doi:10.3762/bjoc.13.14
- systems destructive to the majority of devices manufactured via stereolithography, polymer jetting and fused deposition modelling processes previously utilised for this application. These devices were integrated with commercially available flow chemistry, chromatographic and spectroscopic analysis
- solvents and reagents, making it ideally suited to continuous flow chemistry. The part was again tested using the semicarbazide preparation previously outlined (Scheme 1), and automated through the Chemstation software. For this optimisation an 1100 series binary pump module was used to pump the two
Extrusion – back to the future: Using an established technique to reform automated chemical synthesis
Beilstein J. Org. Chem. 2017, 13, 65–75, doi:10.3762/bjoc.13.9
- continuous flow chemistry is typically very narrow of several millimetres. Furthermore, the kneading segments can be positioned at angles of 30o, 60o and 90o relative to each other, with the latter angle providing the greatest kneading (and shear). The kneading section can be quite hostile as it involves not
Green chemistry
Beilstein J. Org. Chem. 2016, 12, 2763–2765, doi:10.3762/bjoc.12.273
- reactivity of a chemical process and may facilitate the recovery and reuse of the materials used, which contribute to minimizing the energy consumption and increasing the overall efficiency of a process. Flow chemistry, microwave or ultrasonic irradiation, and mechano-chemistry are just a few representative
Continuous-flow synthesis of primary amines: Metal-free reduction of aliphatic and aromatic nitro derivatives with trichlorosilane
Beilstein J. Org. Chem. 2016, 12, 2614–2619, doi:10.3762/bjoc.12.257
- . Flow chemistry has recently emerged as a powerful technology in synthetic chemistry [12] as it can reduce risks associated to the use of hazardous chemicals and favors reaction scale-up [13][14][15][16][17]. The possibility to efficiently perform nitro reduction in continuo would make the
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