Optimizing reaction conditions for the light-driven hydrogen evolution in a loop photoreactor

• Pengcheng Li,
• Daniel Kowalczyk,
• Johannes Liessem,
• Mohamed M. Elnagar,
• Dariusz Mitoraj,
• Radim Beranek and
• Dirk Ziegenbalg

Beilstein J. Org. Chem. 2024, 20, 74–91, doi:10.3762/bjoc.20.9

• (LEDs) have plenty of advantages including long life span (up to 100 000 h), robustness, compact size, and high energy efficiency, which make LEDs very attractive as a light source for photocatalytic hydrogen generation studies [29]. In this work, a loop photoreactor for scaling up the photocatalytic

Biphenylene-containing polycyclic conjugated compounds

• Cagatay Dengiz

Beilstein J. Org. Chem. 2023, 19, 1895–1911, doi:10.3762/bjoc.19.141

• ] cycloaddition [19][20], [2 + 2 + 2] cycloaddition [21], and the Ullmann reaction [15][22] (Scheme 1). Due to the observed low yields in flash vacuum pyrolysis, the difficulty in synthesizing starting materials, such as 3, and the impractical nature of scaling up the method for large quantities, the other three

Selective and scalable oxygenation of heteroatoms using the elements of nature: air, water, and light

• Damiano Diprima,
• Hannes Gemoets,
• Stefano Bonciolini and
• Koen Van Aken

Beilstein J. Org. Chem. 2023, 19, 1146–1154, doi:10.3762/bjoc.19.82

• implementation. The protocol utilizes oxygen or air, a water-based solution, and UV-A irradiation at 365 nm. Scaling up such protocols has traditionally been difficult, as demonstrated by a previous oxidation of thioanisole on a 10 g scale, which had a long reaction time of 13 hours [29]. Advantageously, our

Photoredox catalysis harvesting multiple photon or electrochemical energies

• Mattia Lepori,
• Simon Schmid and
• Joshua P. Barham

Beilstein J. Org. Chem. 2023, 19, 1055–1145, doi:10.3762/bjoc.19.81

• providing products 4a and 17k in very good yields and gram-scale per hour productivities demonstrating the ease of scaling up conPET reactions in continuous flow. In general, standardized flow photoreactors which are already widely available enable immediate integration of conPET reactions. On the other

Linker, loading, and reaction scale influence automated glycan assembly

• Marlene C. S. Dal Colle,
• Manuel G. Ricardo,
• Nives Hribernik,
• José Danglad-Flores,
• Peter H. Seeberger and
• Martina Delbianco

Beilstein J. Org. Chem. 2023, 19, 1015–1020, doi:10.3762/bjoc.19.77

• , the results showed minimal variation within each series of experiments, indicating that loading and reaction scale are not significantly affecting AGA of those sequences within the range of conditions explored here. This is a promising observation from the perspective of scaling up AGA. No differences

C3-Alkylation of furfural derivatives by continuous flow homogeneous catalysis

• Grédy Kiala Kinkutu,
• Catherine Louis,
• Myriam Roy,
• Juliette Blanchard and
• Julie Oble

Beilstein J. Org. Chem. 2023, 19, 582–592, doi:10.3762/bjoc.19.43

• .19.43 Abstract The C3-functionalization of furfural using homogeneous ruthenium catalysts requires the preinstallation of an ortho-directing imine group, as well as high temperatures, which did not allow scaling up, at least under batch conditions. In order to design a safer process, we set out to

• in the scaling up of our reactions. To our great satisfaction, we could show that the productivity of the flow chemistry approach is better than the batch approach with the same catalyst (Scheme 8). This strategy represents a novel method to produce functionalized furfurals, providing synthetically

• derivative alkylation reaction. Scaling up comparison: batch and continuous flow conditions. Optimization of the catalyst for the alkylation reaction on the homemade pulsed-flow setup. Optimization of the alkylation reaction directly from furfural on the continuous flow setup. Supporting Information

A new oxidatively stable ligand for the chiral functionalization of amino acids in Ni(II)–Schiff base complexes

• Alena V. Dmitrieva,
• Oleg A. Levitskiy,
• Yuri K. Grishin and
• Tatiana V. Magdesieva

Beilstein J. Org. Chem. 2023, 19, 566–574, doi:10.3762/bjoc.19.41

• complex. Solubility of the t-Bu-containing ligand and its Schiff base complexes is increased, facilitating scaling-up the reaction procedure and isolation of the functionalized amino acid. Keywords: asymmetric synthesis; chiral auxiliaries; cysteine derivatives; Ni–Schiff base complexes; voltammetry

• controlled stereoselectivity. Finally, the solubility of the t-Bu-containing ligand and its Schiff base complexes is increased, facilitating scaling-up the reaction procedure and isolation of the functionalized amino acid. We hope that the chiral templates derived from the easily available and inexpensive

Modern flow chemistry – prospect and advantage

• Philipp Heretsch

Beilstein J. Org. Chem. 2023, 19, 33–35, doi:10.3762/bjoc.19.3

• small dimensions of flow reactors enable explosive, toxic, or otherwise dangerous reactions and reagents to be accumulated only to a much lesser degree, especially when scaling up. This virtue has been exploited in process chemistry, where in the manufacturing of HIV protease inhibitor nelfinavir

One-pot synthesis of 2-arylated and 2-alkylated benzoxazoles and benzimidazoles based on triphenylbismuth dichloride-promoted desulfurization of thioamides

• Arisu Koyanagi,
• Yuki Murata,
• Shiori Hayakawa,
• Mio Matsumura and
• Shuji Yasuike

Beilstein J. Org. Chem. 2022, 18, 1479–1487, doi:10.3762/bjoc.18.155

• reacted in the presence of 6a in 1,2-DCE at 60 °C under aerobic conditions. The optimal reagent, Ph3BiCl2 (6a), can be easily and inexpensively synthesized on a 10 g scale by scaling up the reported procedure (see Supporting Information File 1) [36][37]. To investigate the efficiency and generality of the

Cryogels: recent applications in 3D-bioprinting, injectable cryogels, drug delivery, and wound healing

• Luke O. Jones,
• Leah Williams,
• Tasmin Boam,
• Martin Kalmet,
• Chidubem Oguike and
• Fiona L. Hatton

Beilstein J. Org. Chem. 2021, 17, 2553–2569, doi:10.3762/bjoc.17.171

A comprehensive review of flow chemistry techniques tailored to the flavours and fragrances industries

• Guido Gambacorta,
• James S. Sharley and
• Ian R. Baxendale

Beilstein J. Org. Chem. 2021, 17, 1181–1312, doi:10.3762/bjoc.17.90

A chromatography-free and aqueous waste-free process for thioamide preparation with Lawesson’s reagent

• Ke Wu,
• Yichen Ling,
• An Ding,
• Liqun Jin,
• Nan Sun,
• Baoxiang Hu,
• Zhenlu Shen and
• Xinquan Hu

Beilstein J. Org. Chem. 2021, 17, 805–812, doi:10.3762/bjoc.17.69

• scaling up the preparation of two pincer-type thioamides, we have successfully developed a convenient process with ethylene glycol to replace ethanol during the workup, including a traditional phase separation, extraction, and recrystallization. The newly developed chromatography-free procedure did not

• ]. This method with long perfluorinated alkyl chains is attractive in parallel synthesis and also in high-throughput biological screening. However, both the modified LR and the fluorous solvents are rather expensive and not practical for scaling up. Besides, basic aqueous solutions were utilized as well

• aqueous waste. The P-containing aqueous waste is unfavorable during the scaling up because of the difficult treatment in the downstream and also because it is one of the sources of eutrophication. Therefore, optimizing the work-up process of LR-mediated thionation reactions is greatly appealing for

Ultrasound-assisted Strecker synthesis of novel 2-(hetero)aryl-2-(arylamino)acetonitrile derivatives

• Emese Gal,
• Luiza Gaina,
• Hermina Petkes,
• Alexandra Pop,
• Castelia Cristea,
• Gabriel Barta,
• Dan Cristian Vodnar and
• Luminiţa Silaghi-Dumitrescu

Beilstein J. Org. Chem. 2020, 16, 2929–2936, doi:10.3762/bjoc.16.242

• ]. A major benefit of sonocrystallization appeared to be the induction of nucleation and therefore, crystallization improvements were operated for several organic compounds of low to medium molecular weight with the possibility of scaling up of this technology for industrial use [7]. Low ultrasonic

Dawn of a new era in industrial photochemistry: the scale-up of micro- and mesostructured photoreactors

• Emine Kayahan,
• Mathias Jacobs,
• Leen Braeken,
• Leen C.J. Thomassen,
• Simon Kuhn,
• Tom van Gerven and
• M. Enis Leblebici

Beilstein J. Org. Chem. 2020, 16, 2484–2504, doi:10.3762/bjoc.16.202

• platform for enhancing the photoreaction rates and easier scale-up. One of the hurdles in scaling up of photoreactors is the lack of a consensus on a benchmark to compare different scales and geometries. The simplest benchmark is the apparent rate constant kapp [12][13][14][15] shown in Equation 1. where

• and the problems related to scaling up are comparable. Our aim is to give an overview on the scale-up of photochemical reactions by discussing transport phenomena and technical challenges. In addition, we are assessing several high-throughput structured photoreactors using the PSTY to reveal the

• in the next section. Scaling up and energy efficiency Photoreactors cannot be scaled up by the conventional strategy of enlarging the dimensions due to the light attenuation effect. The heterogeneous flow dynamics and the light field complicate the design further. As a result, photochemical processes

Heterogeneous photocatalysis in flow chemical reactors

• Christopher G. Thomson,
• Ai-Lan Lee and
• Filipe Vilela

Beilstein J. Org. Chem. 2020, 16, 1495–1549, doi:10.3762/bjoc.16.125

• LEDs, which could be problematic when scaling up. Additionally, the attrition of the free floating TiO2@WLE spheres, leading to potential damage or leaching of the TiO2 layer, was not investigated. The excellent chemical and thermal stability of metal alloys makes them ideal supports for applications

A method to determine the correct photocatalyst concentration for photooxidation reactions conducted in continuous flow reactors

• Clemens R. Horn and
• Sylvain Gremetz

Beilstein J. Org. Chem. 2020, 16, 871–879, doi:10.3762/bjoc.16.78

• the combination of light, the “greenest reagent” oxygen, and a catalyst as well as applying mild process conditions under process-intensified conditions can be considered a very sustainable setup [12][13][14]. The scaling-up of photoflow reactors has also been affected by the increased use of LED

Opening up connectivity between documents, structures and bioactivity

• Christopher Southan

Beilstein J. Org. Chem. 2020, 16, 596–606, doi:10.3762/bjoc.16.54

• enable open science data mining at all scales. This applies not only to individual documents (i.e., small data) but scaling up to all papers and patents (i.e., big data). The potential of the latter is huge, especially since artificial intelligence (AI) is being increasingly applied to knowledge

Asymmetric synthesis of a high added value chiral amine using immobilized ω-transaminases

• Antonella Petri,
• Valeria Colonna and
• Oreste Piccolo

Beilstein J. Org. Chem. 2019, 15, 60–66, doi:10.3762/bjoc.15.6

• reaction parameters were studied to optimize the protocol for further scaling-up purposes. Results and Discussion In order to obtain enantiomerically pure (R)- and (S)-3-amino-1-Boc-piperidine (2), the transamination reaction was studied by using commercially available immobilized TAs (TAs-IMB) and

A general and atom-efficient continuous-flow approach to prepare amines, amides and imines via reactive N-chloramines

• Katherine E. Jolley,
• Michael R. Chapman and
• A. John Blacker

Beilstein J. Org. Chem. 2018, 14, 2220–2228, doi:10.3762/bjoc.14.196

• under an atmosphere of air or in the presence of TEMPO, suppressed all product formation (Table 2, entry 5). Due to the safety concerns of scaling-up such a batch reaction, a heated single-stage CSTR was evaluated to immediately quench the N-chloramine. Flowing an aqueous solution of in situ generated

Functionalization of N-arylglycine esters: electrocatalytic access to C–C bonds mediated by n-Bu₄NI

• Mi-Hai Luo,
• Yang-Ye Jiang,
• Kun Xu,
• Yong-Guo Liu,
• Bao-Guo Sun and
• Cheng-Chu Zeng

Beilstein J. Org. Chem. 2018, 14, 499–505, doi:10.3762/bjoc.14.35

• given. Scaling up. Control experiments. A plausible mechanism for the electrocatalytic cross dehydrogenative coupling of N-arylglycine esters with C-nucleophiles. Optimization of reaction conditionsa. Supporting Information Supporting Information File 98: General procedure and analytical data

Correction: Mechanochemical enzymatic resolution of N-benzylated-β³-amino esters

• Mario Pérez-Venegas,
• Gloria Reyes-Rangel,
• Adrián Neri,
• Jaime Escalante and
• Eusebio Juaristi

Beilstein J. Org. Chem. 2017, 13, 2128–2130, doi:10.3762/bjoc.13.210

• under ball milling. Substrate scope for the enzymatic resolution of N-benzylated-β3-amino esters. Recycling capacity of immobilized CALB under HSBM conditions. Scaling-up of the enzymatic hydrolysis reaction under ball-milling using substrate rac-1a. Supporting Information Supporting Information File

Mechanochemical enzymatic resolution of N-benzylated-β³-amino esters

• Mario Pérez-Venegas,
• Gloria Reyes-Rangel,
• Adrián Neri,
• Jaime Escalante and
• Eusebio Juaristi

Beilstein J. Org. Chem. 2017, 13, 1728–1734, doi:10.3762/bjoc.13.167

• -benzylated-β3-amino esters. Recycling capacity of immobilized CALB under HSBM conditions. Scaling-up of the enzymatic hydrolysis reaction under ball-milling using substrate rac-1a. Supporting Information Supporting Information File 254: Experimental section, NMR spectra, chromatograms and X-ray diffraction

Synthesis of oligonucleotides on a soluble support

• Harri Lönnberg

Beilstein J. Org. Chem. 2017, 13, 1368–1387, doi:10.3762/bjoc.13.134

• Harri Lonnberg Department of Chemistry, University of Turku, FIN-20014 Turku, Finland 10.3762/bjoc.13.134 Abstract Oligonucleotides are usually prepared in lab scale on a solid support with the aid of a fully automated synthesizer. Scaling up of the equipment has allowed industrial synthesis up

New tricks of well-known aminoazoles in isocyanide-based multicomponent reactions and antibacterial activity of the compounds synthesized

• Maryna V. Murlykina,
• Maryna N. Kornet,
• Sergey M. Desenko,
• Svetlana V. Shishkina,
• Oleg V. Shishkin,
• Aleksander A. Brazhko,
• Vladimir I. Musatov,
• Erik V. Van der Eycken and
• Valentin A. Chebanov

Beilstein J. Org. Chem. 2017, 13, 1050–1063, doi:10.3762/bjoc.13.104

• while scaling up the production of biomass with the aim of shortening the time and saving resources [120][121]. Although this is a subject for a future detailed study the results of antibacterial activity allowed outlining the positive tendency. Conclusion In summary, the behavior of 5-amino-N-aryl-1H

Automating multistep flow synthesis: approach and challenges in integrating chemistry, machines and logic

• Chinmay A. Shukla and
• Amol A. Kulkarni

Beilstein J. Org. Chem. 2017, 13, 960–987, doi:10.3762/bjoc.13.97