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Search for "flow chemistry" in Full Text gives 121 result(s) in Beilstein Journal of Organic Chemistry.
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
Development of a continuous process for α-thio-β-chloroacrylamide synthesis with enhanced control of a cascade transformation
Beilstein J. Org. Chem. 2016, 12, 2511–2522, doi:10.3762/bjoc.12.246
- -chloroacrylamides; cascade reactions; flow chemistry; Introduction Since the efficient and highly stereoselective transformation of α-thioamides to the corresponding α-thio-β-chloroacrylamides derivatives was first reported [1][2], the considerable synthetic utility of these heavily functionalized acrylamide
- facilitate significant ease of scale-up. The reaction control afforded by use of high surface-area-to-volume ratio tubular reactors, specifically with respect to dissipation of heat, offers a safety profile unique to flow chemistry. Continuous processing also provides the capacity to continuously generate
- ′-methylphenyl-(Z)-3-chloro-2-(phenylthio)propenamide (Z-3) as the target product. This optimized process would utilise flow chemistry as a key enabling technology to overcome the aforementioned challenges. Results and Discussion Preparation of α-chloroamide The synthesis of α-chloroamide 1 is highly exothermic
A flow reactor setup for photochemistry of biphasic gas/liquid reactions
Beilstein J. Org. Chem. 2016, 12, 1798–1811, doi:10.3762/bjoc.12.170
- operation of various other reactions at light/liquid/gas interfaces in student, research, and industrial laboratories. Keywords: biphasic reactions; flow chemistry; gas phase; microreactor; oxygen; photochemistry; Introduction The recent developments of microreactor technologies have significantly
Catalytic Chan–Lam coupling using a ‘tube-in-tube’ reactor to deliver molecular oxygen as an oxidant
Beilstein J. Org. Chem. 2016, 12, 1598–1607, doi:10.3762/bjoc.12.156
- oxygen accelerating the optimisation phase and allowing easy access to elevated pressures. A small exemplification library of heteroaromatic products has been prepared and the process has been shown to be robust over extended reaction times. Keywords: Chan–Lam coupling; flow chemistry; gases in flow
- modification can reliably deliver 0.216 g h−1 of 19 at 81% isolated yield. Conclusion The use of flow chemistry for the C–N coupling through a catalytic Chan–Lam reaction has allowed for a safe and efficient introduction of oxygen through a reverse “tube-in-tube” reactor. Optimisation of the reaction
Flow carbonylation of sterically hindered ortho-substituted iodoarenes
Beilstein J. Org. Chem. 2016, 12, 1503–1511, doi:10.3762/bjoc.12.147
- via a reverse “tube-in-tube” flow reactor at elevated pressures to give yields of carboxylated products that are much higher than those obtained under normal batch conditions. Keywords: carbon monoxide; carbonylation of ortho-substituted substrates; flow chemistry; gases in flow; “tube-in-tube
- monoxide concentration and temperature is critical to obtaining a good yield of carbonylated ortho-substituted products. Results and Discussion The application of flow chemistry [19][20] has been shown to be beneficial for many reactions that involve gases [21][22][23][24][25][26][27][28][29]. The
- h−1 of 20 in 85% isolated yield. Conclusion We have successfully demonstrated how flow chemistry can be used to enhance difficult transformations such as the palladium-catalysed hydroxy-carbonylation of ortho-substituted iodoarenes. The optimised conditions were also demonstrated to work on a number
Continuous formation of N-chloro-N,N-dialkylamine solutions in well-mixed meso-scale flow reactors
Beilstein J. Org. Chem. 2015, 11, 2408–2417, doi:10.3762/bjoc.11.262
- solutions of N,N-dialkyl-N-chloramines produced continuously will enable their use in tandem flow reactions with a range of nucleophilic substrates. Keywords: amine; biphasic; chloramine; chlorination; continuous flow chemistry; CSTR; static mixer; sodium hypochlorite; tube reactor; Introduction N
The synthesis of active pharmaceutical ingredients (APIs) using continuous flow chemistry
Beilstein J. Org. Chem. 2015, 11, 1194–1219, doi:10.3762/bjoc.11.134
- synthetic capabilities. As a result many new preparative routes have been designed towards commercially relevant drug compounds achieving more efficient and reproducible manufacture. This review article aims to illustrate the holistic systems approach and diverse applications of flow chemistry to the
- selected syntheses using micro or meso-scaled flow reactors will be exemplified for key transformations and process control. It is hoped that the reader will gain an appreciation of the innovative technology and transformational nature that flow chemistry can leverage to an overall process. Keywords
- . Arguably one of the most widely amenable of the enabling technologies is flow chemistry, which accommodates small foot-print reactors in which streams of substrates and reagents can be united to react in a highly controlled and reproducible environment [7][8][9][10][11][12][13][14][15]. Importantly
Photocatalytic nucleophilic addition of alcohols to styrenes in Markovnikov and anti-Markovnikov orientation
Beilstein J. Org. Chem. 2015, 11, 568–575, doi:10.3762/bjoc.11.62
- at 530 nm and 59% when irradiated at 470 nm. These irradiations were performed with the corresponding LEDs and yields were identical with conversions. Finally, the nucleophilic addition of methanol to 1 using PDI as photocatalyst was representatively executed in two mesoflow reactors, since flow
- chemistry has significant advantages over batch chemistry, such as easier temperature control, larger surface-to-volume ratio and more efficient photoirradiation. Two setups were used to transfer the reaction to continuous-flow systems. The first mesoflow reactor was equipped with four 250 mW high-power
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