Advances in the use of metal-free tetrapyrrolic macrocycles as catalysts

• Mandeep K. Chahal

Beilstein J. Org. Chem. 2024, 20, 3085–3112, doi:10.3762/bjoc.20.257

• concluded that both the presence of hydrogen-bond donor moieties (pyrrolic –NH groups) and a basic β-substituent are necessary to make the compound catalytically active. Further, authors have performed 1H NMR binding and kinetic studies and suggested that the reaction mechanism involves a simultaneous

Extension of the π-system of monoaryl-substituted norbornadienes with acetylene bridges: influence on the photochemical conversion and storage of light energy

• Robin Schulte,
• Dustin Schade,
• Thomas Paululat,
• Till J. B. Zähringer,
• Christoph Kerzig and
• Heiko Ihmels

Beilstein J. Org. Chem. 2024, 20, 3061–3068, doi:10.3762/bjoc.20.254

• that the triplet energy of 1i is significantly lower than 2.4 eV and even triplet sensitizers with lower triplet energies than that of [Ru(phen)3](PF6)2 could be employed for this reaction, which might even allow red light-driven switching. In addition to these kinetic studies, the photoisomerization

Copper-catalyzed yne-allylic substitutions: concept and recent developments

• Shuang Yang and
• Xinqiang Fang

Beilstein J. Org. Chem. 2024, 20, 2739–2775, doi:10.3762/bjoc.20.232

• confirmed that a copper–ligand monomer complex exists in the mechanism through nonlinear relationship experiments and kinetic studies (Scheme 17). He et al. [68] developed the regio- and enantioselective monofluoroalkylation of yne-allylic esters using fluorinated malonates as the starting materials, giving

Asymmetric organocatalytic synthesis of chiral homoallylic amines

• Nikolay S. Kondratyev and
• Andrei V. Malkov

Beilstein J. Org. Chem. 2024, 20, 2349–2377, doi:10.3762/bjoc.20.201

• -, 3,5-di(trifluormethyl)- and 3,5-dicyanophenylsquaramides, the latter proved to be the most active but all three provided a similar enantioselectivity. Kinetic studies revealed that the reaction displayed the 1st order in both the allyl reagent and the glycinate substrate, which may indicate either a

The Groebke–Blackburn–Bienaymé reaction in its maturity: innovation and improvements since its 21st birthday (2019–2023)

• Cristina Martini,
• Muhammad Idham Darussalam Mardjan and
• Andrea Basso

Beilstein J. Org. Chem. 2024, 20, 1839–1879, doi:10.3762/bjoc.20.162

• diaryliodonium triflates such as 8 and 9 [13]. They studied a model reaction with 2-aminopyridine (1), p-tolualdehyde (10) and cyclohexyl isocyanide (11) both experimentally (by binding and kinetic studies) and theoretically (by density functional theory (DFT) calculations) (Scheme 5). Catalyst 8 was found to be

Hypervalent iodine-catalyzed amide and alkene coupling enabled by lithium salt activation

• Akanksha Chhikara,
• Fan Wu,
• Navdeep Kaur,
• Prabagar Baskaran,
• Alex M. Nguyen,
• Zhichang Yin,
• Anthony H. Pham and
• Wei Li

Beilstein J. Org. Chem. 2024, 20, 1405–1411, doi:10.3762/bjoc.20.122

• less coordinating counterion is more reactive to activate the olefin. We also conducted kinetic studies on how the olefin and amide structures impacted the overall reaction rate. The more electron-rich olefins generally proceeded faster than the electron-poor ones, suggesting that a significant

• cycle for the hypervalent iodine-catalyzed amide and alkene coupling. Hypervalent iodine-catalyzed olefin difunctionalizations background. Amide and alkene reaction optimization studies. Supporting Information Supporting Information File 14: Spectral characterization of the products and kinetic studies

Advancements in hydrochlorination of alkenes

• Daniel S. Müller

Beilstein J. Org. Chem. 2024, 20, 787–814, doi:10.3762/bjoc.20.72

• a side note, it should be mentioned that Hutchings and colleagues reported the hydrochlorination of ethylene with Lewis acids on solid supports [52]. However, this work solely focuses on kinetic studies and is therefore not discussed in this report. Reactions with in situ-generated HCl HCl gas can

Ligand effects, solvent cooperation, and large kinetic solvent deuterium isotope effects in gold(I)-catalyzed intramolecular alkene hydroamination

• Ruichen Lan,
• Brock Yager,
• Yoonsun Jee,
• Cynthia S. Day and
• Amanda C. Jones

Beilstein J. Org. Chem. 2024, 20, 479–496, doi:10.3762/bjoc.20.43

• Ruichen Lan Brock Yager Yoonsun Jee Cynthia S. Day Amanda C. Jones Chemistry, Wake Forest University, 1834 Gulley Rd., Winston-Salem, NC, 27109, USA 10.3762/bjoc.20.43 Abstract Kinetic studies on the intramolecular hydroamination of protected variants of 2,2-diphenylpent-4-en-1-amine were carried

Synthesis of 2,2-difluoro-1,3-diketone and 2,2-difluoro-1,3-ketoester derivatives using fluorine gas

• Alexander S. Hampton,
• David R. W. Hodgson,
• Graham McDougald,
• Linhua Wang and
• Graham Sandford

Beilstein J. Org. Chem. 2024, 20, 460–469, doi:10.3762/bjoc.20.41

• corresponding 2,2-difluoroketones [15]. In related kinetic studies concerning the electrophilic 2-fluorination of 1,3-diketones with Selectfluor [16][17], we demonstrated that the rate-determining step for difluorination was enolization of the intermediate 2-fluoro-1,3-diketone. Monofluorination of 1,3

Photochromic derivatives of indigo: historical overview of development, challenges and applications

• Gökhan Kaplan,
• Zeynel Seferoğlu and
• Daria V. Berdnikova

Beilstein J. Org. Chem. 2024, 20, 228–242, doi:10.3762/bjoc.20.23

• photochromic N,N'-diacyl derivatives of indigo, first examples of photochromic indigos containing aromatic N,N'-substituents 1984: first report on intra- and intermolecularly bridged photochromic N,N'-substituted indigos (follow-up studies in 1989, 2021) 1985: detailed kinetic studies of the thermal backward Z

Metal-catalyzed coupling/carbonylative cyclizations for accessing dibenzodiazepinones: an expedient route to clozapine and other drugs

• Amina Moutayakine and
• Anthony J. Burke

Beilstein J. Org. Chem. 2024, 20, 193–204, doi:10.3762/bjoc.20.19

• File 6: Experimental procedures and spectral data (NMR, mass spectra) and key kinetic studies. Funding This work received financial support from the Fundação para a Ciência e Tecnologia (FCT Portugal) through the project UIDB/50006/2020 | UIDP/50006/2020.

Using the phospha-Michael reaction for making phosphonium phenolate zwitterions

• Matthias R. Steiner,
• Max Schmallegger,
• Larissa Donner,
• Johann A. Hlina,
• Christoph Marschner,
• Judith Baumgartner and
• Christian Slugovc

Beilstein J. Org. Chem. 2024, 20, 41–51, doi:10.3762/bjoc.20.6

• donors attached to the alkyl substituent of the phosphonium center (Figure 3). This hypothesis is further supported by the observation of two very different chemical shifts for the two amide protons in the 1H NMR spectrum of 2b in CDCl3 giving resonance at 5.21 and 8.58 ppm. Kinetic studies In the next

• feature considerable contribution of an ylidic resonance structure in the solid state and in aprotic solution. Kinetic studies revealed that the proton transfer from the phenolic hydroxy group to the initially formed zwitterionic adduct bearing the negative charge at the α-carbon to the electron

NMRium: Teaching nuclear magnetic resonance spectra interpretation in an online platform

• Luc Patiny,
• Hamed Musallam,
• Alejandro Bolaños,
• Michaël Zasso,
• Julien Wist,
• Metin Karayilan,
• Eva Ziegler,
• Johannes C. Liermann and
• Nils E. Schlörer

Beilstein J. Org. Chem. 2024, 20, 25–31, doi:10.3762/bjoc.20.4

• a reaction substrate and product or analysis of kinetic studies that include several data points) or overlaying of 2D spectra, for example, to show the different outcomes of related experiments such as COSY/TOCSY or HSQC/HMBC. Students will be enabled to learn these online comparison aspects by

N-Sulfenylsuccinimide/phthalimide: an alternative sulfenylating reagent in organic transformations

• Fatemeh Doraghi,
• Seyedeh Pegah Aledavoud,
• Mehdi Ghanbarlou,
• Bagher Larijani and
• Mohammad Mahdavi

Beilstein J. Org. Chem. 2023, 19, 1471–1502, doi:10.3762/bjoc.19.106

• an effective catalysis system (Scheme 29) [63]. Kinetic studies in this cross coupling-reaction indicated that N-(arylthio)succinimides 1 with electron-deficient arene 4 undergoe thioarylation catalyzed by Fe(NTf2)3. Related molecules bearing an electron-rich arene showed an autocatalytic pathway

Dipeptide analogues of fluorinated aminophosphonic acid sodium salts as moderate competitive inhibitors of cathepsin C

• Karolina Wątroba,
• Małgorzata Pawełczak and
• Marcin Kaźmierczak

Beilstein J. Org. Chem. 2023, 19, 434–439, doi:10.3762/bjoc.19.33

• fluorinated aminophosphonates [23][24] with the simultaneous deprotection of the amino group. The free amines were subjected to kinetic studies to investigate their interaction with cathepsin C. The required steps should be simple and fast, and the conditions of the reactions should be as mild as possible

• literature data of the starting esters 5 and 7 literature data [23][24]. A very good correlation of chemical shifts was also observed in the 13C NMR spectra for the key signals from the C1 and C2 atoms (Table 1). Each sample was pure; no byproducts were present. Kinetic studies Due to the homology and

• fluorinated aminophosphonates with the simultaneous deprotection of the amino group. The resulting acids were converted into the corresponding salts. All the reactions proceeded quantitatively. Obtained compounds were subjected to kinetic studies against cathepsin C, and the results indicated that they are

CuAAC-inspired synthesis of 1,2,3-triazole-bridged porphyrin conjugates: an overview

• Dileep Kumar Singh

Beilstein J. Org. Chem. 2023, 19, 349–379, doi:10.3762/bjoc.19.29

• excellent yields using Zn(OAc)2 in a CHCl3/MeOH mixture. Their UV–vis titration study revealed that these host systems exhibit strong anion-binding affinities. Furthermore, with the help of kinetic studies, the absorption efficiency of malachite green dye was investigated by using free-base porphyrins 171a

Insight into oral amphiphilic cyclodextrin nanoparticles for colorectal cancer: comprehensive mathematical model of drug release kinetic studies and antitumoral efficacy in 3D spheroid colon tumors

• Sedat Ünal,
• Gamze Varan,
• Juan M. Benito,
• Yeşim Aktaş and
• Erem Bilensoy

Beilstein J. Org. Chem. 2023, 19, 139–157, doi:10.3762/bjoc.19.14

Cyclodextrin-based Schiff base pro-fragrances: Synthesis and release studies

• Attila Palágyi,
• Jindřich Jindřich,
• Juraj Dian and
• Sophie Fourmentin

Beilstein J. Org. Chem. 2022, 18, 1346–1354, doi:10.3762/bjoc.18.140

• stability towards hydrolysis. Kinetic studies of the imine hydrolysis by NMR For the kinetic studies of the hydrolysis of imino-CDs, we selected the pro-fragrance 3d made from the most common aldehyde – benzaldehyde. The release of the benzaldehyde (2d) was studied by 1H NMR spectroscopy. Aqueous 0.1 M

• 1H, 150.04 MHz for 13C) and Varian UNITYINOVA 400 (399,95 MHz for 1H and 100,58 MHz for 13C) spectrometers. For the kinetic studies, the 1H NMR spectra were acquired on a Varian VNMRS 300 spectrometer (300 MHz for 1H). DMSO-d6 and D2O were used as the solvents. The chemical shift values (δ) are given

• studies of the imine hydrolysis by NMR For the kinetic studies of the hydrolysis of imino-CDs, 6I-benzylideneamino-6I-deoxy-β-cyclodextrin (3d) was chosen. The release of the benzaldehyde was studied by 1H NMR spectroscopy. Aqueous 0.1 M phosphate buffer solutions of pH 1.08, 2.00, 3.00, 4.00, 5.00, 6.00

Shift of the reaction equilibrium at high pressure in the continuous synthesis of neuraminic acid

• Jannis A. Reich,
• Miriam Aßmann,
• Kristin Hölting,
• Paul Bubenheim,
• Jürgen Kuballa and
• Andreas Liese

Beilstein J. Org. Chem. 2022, 18, 567–579, doi:10.3762/bjoc.18.59

• introduced by the coupling of pyruvate to the enzyme was calculated by using the exponential fit. The calculated value is −12.9 ± 5.5 mL/mol (the values at 50 MPa and 89 MPa were considered as outliers and not included in the calculation). Kinetic studies of the immobilized aldolase show an increase in

Mechanistic studies of the solvolysis of alkanesulfonyl and arenesulfonyl halides

• Malcolm J. D’Souza and
• Dennis N. Kevill

Beilstein J. Org. Chem. 2022, 18, 120–132, doi:10.3762/bjoc.18.13

• from linearity in Arrhenius plots, which with conventional kinetic studies would be masked by a larger random scatter within the different determinations. A precise detailed treatment allowed the “second-order” heat capacities of activation (∆Cp#) to be determined for, among many other substrates

• temperature variation to investigate this aspect were not reported. In reading the section “Substitutions at Sulphur” in the second edition of Ingold’s classical “Structure and Mechanism in Organic Chemistry” text [53], it is surprising to see that the section starts with the statement “No kinetic studies

Exfoliated black phosphorous-mediated CuAAC chemistry for organic and macromolecular synthesis under white LED and near-IR irradiation

• Azra Kocaarslan,
• Zafer Eroglu,
• Önder Metin and
• Yusuf Yagci

Beilstein J. Org. Chem. 2021, 17, 2477–2487, doi:10.3762/bjoc.17.164

• at 4.42 ppm and appearance of the new signal at 8.67 ppm corresponding to the triazole moiety confirmed successful click reaction under white LED exposure conditions after 4 h (Figure 3a). Kinetic studies conducted by 1H NMR analysis confirmed that the click reaction between benzyl azide and

Development of N-F fluorinating agents and their fluorinations: Historical perspective

• Teruo Umemoto,
• Yuhao Yang and
• Gerald B. Hammond

Beilstein J. Org. Chem. 2021, 17, 1752–1813, doi:10.3762/bjoc.17.123

CF₃-substituted carbocations: underexploited intermediates with great potential in modern synthetic chemistry

• Anthony J. Fernandes,
• Armen Panossian,
• Bastien Michelet,
• Agnès Martin-Mingot,
• Frédéric R. Leroux and
• Sébastien Thibaudeau

Beilstein J. Org. Chem. 2021, 17, 343–378, doi:10.3762/bjoc.17.32

• environment will be scrutinized. The chapter will summarize kinetic studies and concomitant theoretical investigations on the cations formation and stability data as well as synthetic perspectives offered by the studied carbenium ions. Any discussion of the results coming from the ionization of perfluorinated

Diels–Alder reaction of β-fluoro-β-nitrostyrenes with cyclic dienes

• Savva A. Ponomarev,
• Roman V. Larkovich,
• Alexander S. Aldoshin,
• Andrey A. Tabolin,
• Sema L. Ioffe,
• Jonathan Groß,
• Till Opatz and
• Valentine G. Nenajdenko

Beilstein J. Org. Chem. 2021, 17, 283–292, doi:10.3762/bjoc.17.27

• , whereas in the absence of a strong EWG, the ratio was about 1:1 (3a). However, in contrast to CPD derivatives, the major products formed in the reaction with CHD have exo-configuration. To gain deeper insights into the reaction, we carried out some kinetic studies to evaluate and compare the reactivities

One-pot synthesis of isosorbide from cellulose or lignocellulosic biomass: a challenge?

• Isaline Bonnin,
• Raphaël Mereau,
• Thierry Tassaing and
• Karine De Oliveira Vigier

Beilstein J. Org. Chem. 2020, 16, 1713–1721, doi:10.3762/bjoc.16.143

• particular, in situ kinetic studies by spectroscopic methods [31] correlated to computational chemistry approaches [32] might reveal specific interaction between reactants and catalysts as well as solvent effects at work in such a complex system that should provide an understanding of the underlying reason

• for the observed unique kinetics, yields and selectivity in these one-pot reactions. In addition, such in-depth fundamental mechanistic and kinetic studies should enable determining the key structural parameters of the catalytic platform that govern its efficiency hence supporting the design of novel