Advancements in hydrochlorination of alkenes

• Daniel S. Müller

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

• be generated in situ through the reaction of "reactive" chlorides with a proton donor. For instance, the reaction of acetyl chloride with ethanol is exothermic, accompanied by vigorous HCl gas evolution. It is crucial to emphasize that HCl solutions in MeOH, produced from AcCl and MeOH, pose

• hydrochlorination of 1-octene (63) required a combination of alumina and oxalyl chloride (Table 5, entry 3). It should be noted that this reaction needs to be carried out under a well-ventilated hood due to the evolution of toxic carbon monoxide. Kropp and co-workers observed that the remaining 2% of the alkene was

Research progress on the pharmacological activity, biosynthetic pathways, and biosynthesis of crocins

• Zhongwei Hua,
• Nan Liu and
• Xiaohui Yan

Beilstein J. Org. Chem. 2024, 20, 741–752, doi:10.3762/bjoc.20.68

• duplication events during genome evolution [96]. When expressed in the callus of Nicotiana tabacum, GjCCD4a exhibited a higher efficiency in carotenoid cleavage than CsCCD4a [85]. ALDHs: ALDH utilizes NAD+ or NADP+ as cofactor to catalyze the oxidation of acetaldehyde into carboxylic acids. In 2018, Demurtas

• activity. Screening of novel enzymes for crocin biosynthesis and the directed evolution of known enzymes should facilitate the high-titer production of the key intermediates 5–7 etc. and the efficient conversion of these precursors into crocetin (1) and crocins. In conclusion, crocins are high-value plant

Genome mining of labdane-related diterpenoids: Discovery of the two-enzyme pathway leading to (−)-sandaracopimaradiene in the fungus Arthrinium sacchari

• Fumito Sato,
• Terutaka Sonohara,
• Shunta Fujiki,
• Akihiro Sugawara,
• Yohei Morishita,
• Taro Ozaki and
• Teigo Asai

Beilstein J. Org. Chem. 2024, 20, 714–720, doi:10.3762/bjoc.20.65

• AsCPS synthesized copalyl diphosphate and that AsPS then converted it to (−)-sandaracopimaradiene. Since AsPS and AsCPS have distinct domain organizations from those of known fungal TCs and are likely generated through fusion or loss of catalytic domains, our findings provide insight into the evolution

• organizations were discovered, these enzymes would be useful to discuss and further analyze the evolution of TCs in fungi. LRDs in fungi. A) Chemical structures of representative fungal LRDs. B) Reactions catalyzed by selected fungal bifunctional TCs. Sequence analysis of AsPS and AsCPS. A) Biosynthetic gene

Recent developments in the engineered biosynthesis of fungal meroterpenoids

• Zhiyang Quan and
• Takayoshi Awakawa

Beilstein J. Org. Chem. 2024, 20, 578–588, doi:10.3762/bjoc.20.50

• 31 into 37 and 38 (Figure 7B). These results exemplify the production of oxidized terpenoids and meroterpenoids through the use of non-natural substrates and the application of structure-based mutagenesis. Evolution of αKG-dependent dioxygenase with saturated mutagenesis As meroterpenoids readily

Switchable molecular tweezers: design and applications

• Pablo Msellem,
• Maksym Dekthiarenko,
• Nihal Hadj Seyd and
• Guillaume Vives

Beilstein J. Org. Chem. 2024, 20, 504–539, doi:10.3762/bjoc.20.45

• Schrader [3][4], and more flexible variants by Rebek [5][6], Zimmerman [7][8], Bosnich [9] and others [10][11][12]. Initially serving as agents for guest binding and recognition, molecular tweezers have undergone a remarkable evolution, diversifying their applications into the realms of biology, catalysis

Elucidating the glycan-binding specificity and structure of Cucumis melo agglutinin, a new R-type lectin

• Jon Lundstrøm,
• Emilie Gillon,
• Valérie Chazalet,
• Nicole Kerekes,
• Antonio Di Maio,
• Ten Feizi,
• Yan Liu,
• Annabelle Varrot and
• Daniel Bojar

Beilstein J. Org. Chem. 2024, 20, 306–320, doi:10.3762/bjoc.20.31

• , by extension, common folds [12]. Still, shared binding specificity does not always follow from structural similarity, exemplified by divergent evolution within lectin families as well as independent emergence of similar binding patterns [13]. Many of the most commonly used lectins for the

Synthesis of π-conjugated polycyclic compounds by late-stage extrusion of chalcogen fragments

• Aissam Okba,
• Pablo Simón Marqués,
• Kyohei Matsuo,
• Naoki Aratani,
• Hiroko Yamada,
• Gwénaël Rapenne and
• Claire Kammerer

Beilstein J. Org. Chem. 2024, 20, 287–305, doi:10.3762/bjoc.20.30

• -resolution STM and AFM images, revealing the linear fusion of benzene rings with a zigzag edge (Figure 3), and their electronic properties were investigated at the single-molecule scale, with a particular attention devoted to the evolution of the HOMO–LUMO gap along the incremental series of acenes

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

• . 2, 57076 Siegen, Germany 10.3762/bjoc.20.23 Abstract The importance of indigo dyes is constantly increasing with the evolution of novel textile materials and photochromic material technologies. The aim of this review article is to provide a comprehensive overview of the development of photochromic

Perspectives on push–pull chromophores derived from click-type [2 + 2] cycloaddition–retroelectrocyclization reactions of electron-rich alkynes and electron-deficient alkenes

• Michio Yamada

Beilstein J. Org. Chem. 2024, 20, 125–154, doi:10.3762/bjoc.20.13

• landscape of [2 + 2] CA–RE reactions for the preparation of push–pull chromophores is rapidly evolving and expanding. This evolution necessitates an update on the latest insights for materials science researchers. Furthermore, the diverse research advancements related to the distinctive physicochemical

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

• evolution using a Pt-loaded polymeric carbon nitride photocatalyst under 365 nm irradiation in the presence of sacrificial reducing agents. The fluid flow pattern of the developed photoreactor was characterized experimentally and the photon flux incident to the loop photoreactor was measured by chemical

• generation rate. Linear relationships were found between hydrogen evolution rate and photon flux as well as inert gas flow rate. Photocatalyst loading and stirring speed also showed linear correlations, but could not be correctly described by DOE analysis. Instead, linear single parameter correlations could

• be applied. Notably, the loop photoreactor demonstrated an external photon efficiency up to 17 times higher than reported in literature studies, while scaling the reactor size by a factor of 10. Keywords: loop photoreactor; parametric study; photocatalytic hydrogen evolution; polymeric carbon

Identification of the p-coumaric acid biosynthetic gene cluster in Kutzneria albida: insights into the diazotization-dependent deamination pathway

• Seiji Kawai,
• Akito Yamada,
• Yohei Katsuyama and
• Yasuo Ohnishi

Beilstein J. Org. Chem. 2024, 20, 1–11, doi:10.3762/bjoc.20.1

• diazo group-containing compounds through directed evolution. Finally, this study is important because of the success of genome mining for BGCs in a rare actinomycete, K. albida. Although 47 BGCs were indicated in the K. albida genome by the antiSMASH analysis, only aculeximycin was reported as a natural

1-Butyl-3-methylimidazolium tetrafluoroborate as suitable solvent for BF₃: the case of alkyne hydration. Chemistry vs electrochemistry

• Marta David,
• Elisa Galli,
• Richard C. D. Brown,
• Marta Feroci,
• Fabrizio Vetica and
• Martina Bortolami

Beilstein J. Org. Chem. 2023, 19, 1966–1981, doi:10.3762/bjoc.19.147

• diethyl ether traces and then analysed by NMR to check for BMIm-F presence, whereas the fluoride ion could originate from IL decomposition in the presence of water or from the evolution of electrogenerated F2. However, the 19F NMR spectrum showed no detectable peak around −122 ppm, reported in the

Studying specificity in protein–glycosaminoglycan recognition with umbrella sampling

• Mateusz Marcisz,
• Sebastian Anila,
• Margrethe Gaardløs,
• Martin Zacharias and
• Sergey A. Samsonov

Beilstein J. Org. Chem. 2023, 19, 1933–1946, doi:10.3762/bjoc.19.144

•  1, Figure S4). During the relaxation, again, only a minor decrease in RMSD was observed suggesting that a slightly more favorable pose was achieved. In terms of the energy evolution during pulling away, it started around −140 kcal/mol and then it increased up to the 30th window where it stabilized

Beyond n-dopants for organic semiconductors: use of bibenzo[d]imidazoles in UV-promoted dehalogenation reactions of organic halides

• Kan Tang,
• Megan R. Brown,
• Chad Risko,
• Melissa K. Gish,
• Garry Rumbles,
• Phuc H. Pham,
• Oana R. Luca,
• Stephen Barlow and
• Seth R. Marder

Beilstein J. Org. Chem. 2023, 19, 1912–1922, doi:10.3762/bjoc.19.142

• (Figure 4a) show significant spectral evolution within the first 1 ps following photoexcitation at 350 nm in MeCN. The (negative) bleach feature at 450 nm and photoinduced absorption (PIA) peaking at 775 nm transform into a broad PIA spanning the visible wavelengths with a notable isosbestic point at 600

• nm. There is a secondary evolution occurring with a time constant of approximately 60 ps resulting in a long-lived feature existing beyond the 5 ns window of the ultrafast experiment. In toluene (Figure 4b), the spectral features at early times are different; however, the kinetics at 654 nm are the

• -DMBI)2 with a broad PIA spanning the visible wavelengths, which may suggest that the initial evolution observed in the (N-DMBI)2 occurs within our instrument response. In toluene, the signal amplitude at 5 ns for (Cyc-DMBI)2 is significantly smaller than that of the (N-DMBI)2 and 96% of the signal

N-Boc-α-diazo glutarimide as efficient reagent for assembling N-heterocycle-glutarimide diads via Rh(II)-catalyzed N–H insertion reaction

• Grigory Kantin,
• Pavel Golubev,
• Alexander Sapegin,
• Alexander Bunev and
• Dmitry Dar’in

Beilstein J. Org. Chem. 2023, 19, 1841–1848, doi:10.3762/bjoc.19.136

• and efficiency in various XH insertion reactions [27][28][29]. In many cases (e.g., indoles, indazoles, benzotriazoles, tetrazoles, Scheme 3) the reaction progressed expeditiously (as indicated by gas evolution upon adding diazo reagent to the mixture of NH-substrate and catalyst) and was completed in

Selectivity control towards CO versus H₂ for photo-driven CO₂ reduction with a novel Co(II) catalyst

• Lisa-Lou Gracia,
• Philip Henkel,
• Olaf Fuhr and
• Claudia Bizzarri

Beilstein J. Org. Chem. 2023, 19, 1766–1775, doi:10.3762/bjoc.19.129

• concentration of this greenhouse gas by upcycling. Selectivity towards CO2-reduction products is highly desirable, although it can be challenging to achieve since the metal-hydrides formation is sometimes favored and leads to H2 evolution. In this work, we designed a cobalt-based catalyst, and we present herein

• (versus NHE), respectively [3]. However, the molecular hydrogen evolution might compete, as it occurs at a more favorable reduction potential, lowering the selectivity of the catalytic system. While the addition of a proton source is beneficial to lower the overpotential, a metal-hydride (M–H

• also serve as a reductant [47]. The reduced species PS− can be oxidized back to PS by a molecule of 1, which could detach a −NCS anion and offer a vacant site to coordinate a proton (then following an H2 evolution path) or a molecule of CO2 [46]. The adduct with CO2 is further reduced (by PS− or BI

Quinoxaline derivatives as attractive electron-transporting materials

• Zeeshan Abid,
• Liaqat Ali,
• Sughra Gulzar,
• Faiza Wahad,
• Raja Shahid Ashraf and
• Christian B. Nielsen

Beilstein J. Org. Chem. 2023, 19, 1694–1712, doi:10.3762/bjoc.19.124

• compound with the donor polymer PM6 to create BHJ nanoparticles and employed it in the hydrogen evolution reaction. This approach substantially reduced trap density, increasing the hydrogen evolution rate by 2–3 times compared to conventional inorganic/organic hybrid photocatalysts [30]. Computational

Benzoimidazolium-derived dimeric and hydride n-dopants for organic electron-transport materials: impact of substitution on structures, electrochemistry, and reactivity

• Swagat K. Mohapatra,
• Khaled Al Kurdi,
• Samik Jhulki,
• Georgii Bogdanov,
• John Bacsa,
• Maxwell Conte,
• Tatiana V. Timofeeva,
• Seth R. Marder and
• Stephen Barlow

Beilstein J. Org. Chem. 2023, 19, 1651–1663, doi:10.3762/bjoc.19.121

• not react significantly with VII in solution at room temperature, while the reactions of 12 derivatives and VI are very rapid) [9][14][50][61]. Figure 8a compares the evolution of the absorbance at 1030 nm, corresponding to a VI•– absorption maximum, when doping excess VI with 1H derivatives in

• strongly bound dimers. Figure 8b compares the evolution of one of the distinctive VII •– absorptions when doping VII with excess 12 derivatives in chlorobenzene at 293 K in the absence of light, air, and water. In the case of the Y = 4-dimethylaminophenyl dimers 1b2 and 1g2, the VII•– absorption grows in

• reduction peak, while the reduction peak of the cation is seen in the voltammograms of both 1gH and 1g2 following scanning of the irreversible oxidation peaks. Acceptors used to examine reactivity of DMBI-H and (DMBI)2 derivatives. a) Temporal evolution of the absorbance at 1030 nm, corresponding to an

A series of perylene diimide cathode interlayer materials for green solvent processing in conventional organic photovoltaics

• Kathryn M. Wolfe,
• Shahidul Alam,
• Eva German,
• Fahad N. Alduayji,
• Maryam Alqurashi,
• Frédéric Laquai and
• Gregory C. Welch

Beilstein J. Org. Chem. 2023, 19, 1620–1629, doi:10.3762/bjoc.19.119

• the CILs PDIN-FB, PDIN-B, CN-PDIN-FB, and CN-PDIN-B. Evolution of the dimer tPDI2N-R [23] as an NFA to PDIN-B/PDIN-FB monomers to serve as CILs, where the addition of nitrile functional group on the monomeric PDIN-B/PDIN-FB materials serve to stabilize FMOs. a) Structures of PDIN-FB, PDIN-B, CN-PDIN

Radical chemistry in polymer science: an overview and recent advances

• Zixiao Wang,
• Feichen Cui,
• Yang Sui and
• Jiajun Yan

Beilstein J. Org. Chem. 2023, 19, 1580–1603, doi:10.3762/bjoc.19.116

• and in-depth dialogs between the organic and polymer communities. Therefore, future opportunities for polymer science evolution lie in the collaboration of radical chemists in both communities. Used abbreviations in the text and their explanations are collected in Table 2. Oxidation of catechol and

Unraveling the role of prenyl side-chain interactions in stabilizing the secondary carbocation in the biosynthesis of variexenol B

• Moe Nakano,
• Rintaro Gemma and
• Hajime Sato

Beilstein J. Org. Chem. 2023, 19, 1503–1510, doi:10.3762/bjoc.19.107

• at the mPW1PW91/6-31+G(d,p)//M06-2X/6-31+G(d,p) level) relative to IM1 are shown in parentheses. (A) A representative example of the evolution of key bond lengths in the conversion of path a. (B) Key representative orbitals of TS_2a–3a computed by DFT calculations. Proposed biosynthetic pathway for

Functions of enzyme domains in 2-methylisoborneol biosynthesis and enzymatic synthesis of non-natural analogs

• Binbin Gu,
• Lin-Fu Liang and
• Jeroen S. Dickschat

Beilstein J. Org. Chem. 2023, 19, 1452–1459, doi:10.3762/bjoc.19.104

• for sodorifen [38] – potentially allow for an evolution towards a natural biosynthetic pathway for C12 monoterpenoids. Experimental General synthetic methods Chemicals were purchased from Sigma-Aldrich Chemie GmbH (Steinheim, Germany), Carbolution Chemicals GmbH (St. Ingbert, Germany), or Carl Roth

Radical ligand transfer: a general strategy for radical functionalization

• David T. Nemoto Jr,
• Kang-Jie Bian,
• Shih-Chieh Kao and
• Julian G. West

Beilstein J. Org. Chem. 2023, 19, 1225–1233, doi:10.3762/bjoc.19.90

• decarboxylation. Here, we provide an overview of the evolution of RLT catalysis from initial studies to recent advances and provide a conceptual framework we hope will inspire and enable future work using this versatile elementary step. Keywords: catalysis; cooperative catalysis; earth abundant elements

Enabling artificial photosynthesis systems with molecular recycling: A review of photo- and electrochemical methods for regenerating organic sacrificial electron donors

• Grace A. Lowe

Beilstein J. Org. Chem. 2023, 19, 1198–1215, doi:10.3762/bjoc.19.88

• discharge and charge the donor-containing organic phase (Figure 2A) [34]. The first solution contained an organic lithium salt and a hydrogen-evolution catalyst which could generate hydrogen via a light-driven or dark process. The second solution contained an organic chloride salt and a water oxidation

• photocatalyst which re-reduced DcMFc and evolved oxygen. The same reaction scheme was used but in a modified H-cell (Figure 2B) [35]. Both catalysts were confined at the ITIES in two separate chambers and the redox mediator diffused between the two cells via the organic phase. The protons for hydrogen evolution

• been chosen from literature on redox flow batteries and decoupled hydrogen evolution, as well as photocatalysis. The oxidation and reduction potentials have been collected from various references and were converted to the potential scale vs SCE. Unless otherwise stated, the potentials were recorded in

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

• driving force (evolution of CO2). Triethylphosphite P(OEt)3 and bis(pinacolato)diboron B2pin2 were successfully applied as trapping reagents for redox-neutral photo-Arbuzov and borylation reactions with good to excellent yields (Figure 11D). Additionally, the authors were able to perform the net-reductive