A novel recyclable organocatalyst for the gram-scale enantioselective synthesis of (S)-baclofen

• Gyula Dargó,
• Dóra Erdélyi,
• Balázs Molnár,
• Péter Kisszékelyi,
• Zsófia Garádi and
• József Kupai

Beilstein J. Org. Chem. 2023, 19, 1811–1824, doi:10.3762/bjoc.19.133

• was washed with water (2 × 60 mL), dried over MgSO4, and concentrated in vacuo. The intermediate (1.24 g) was used in the next reaction without purification. The crude, N-Boc-protected intermediate was dissolved in dichloromethane (25 mL) and the solution cooled to 0 °C with an ice bath. Next

Synthetic approach to 2-alkyl-4-quinolones and 2-alkyl-4-quinolone-3-carboxamides based on common β-keto amide precursors

• Yordanka Mollova-Sapundzhieva,
• Plamen Angelov,
• Danail Georgiev and
• Pavel Yanev

Beilstein J. Org. Chem. 2023, 19, 1804–1810, doi:10.3762/bjoc.19.132

• dichloromethane solution of the corresponding keto amide 1 with a slight excess of 70% aqueous ethylamine over Na2SO4 and were used directly in the next step, without purification. These compounds are highly reactive at their α-position towards acylating reagents and this provides an opportunity to prepare the

Active-metal template clipping synthesis of novel [2]rotaxanes

• Cătălin C. Anghel,
• Teodor A. Cucuiet,
• Niculina D. Hădade and
• Ion Grosu

Beilstein J. Org. Chem. 2023, 19, 1776–1784, doi:10.3762/bjoc.19.130

• Information File 1). However, only [2]rotaxane R2 could be isolated as pure compound in 3% yield, after several purification operations by column chromatography. The improved results obtained in the intramolecular macrocyclization for the clipping reaction as compared to the [1 + 1] strategy are in line with

• experimental data Commercially available reagents were used without further purification. Compounds 1 [43][47], 4 [48], 9 [49], 10 [44] and M2 [44] were synthesized according to procedures reported in the literature. Thin-layer chromatography (TLC) was performed on silica gel 60 coated aluminium F254 plates

Unprecedented synthesis of a 14-membered hexaazamacrocycle

• Anastasia A. Fesenko and
• Anatoly D. Shutalev

Beilstein J. Org. Chem. 2023, 19, 1728–1740, doi:10.3762/bjoc.19.126

• purification, the operational simplicity of all the reactions, the high availability of all the reactants make the developed synthesis very promising. A plausible pathway of the hydrazine-promoted self-assembly of the macrocycle from the pyrazolopyrimidine based on the experimental data and the DFT

• the syntheses. Anhydrous N2H4 was obtained from N2H4·H2O according to the standard procedure. All other reagents were purchased from commercial sources and used without additional purification. FTIR spectra were recorded using a Bruker Alpha-T spectrophotometer in KBr. Band characteristics in the IR

Effects of the aldehyde-derived ring substituent on the properties of two new bioinspired trimethoxybenzoylhydrazones: methyl vs nitro groups

• Dayanne Martins,
• Roberta Lamosa,
• Talis Uelisson da Silva,
• Carolina B. P. Ligiero,
• Sérgio de Paula Machado,
• Daphne S. Cukierman and
• Nicolás A. Rey

Beilstein J. Org. Chem. 2023, 19, 1713–1727, doi:10.3762/bjoc.19.125

• -Aldrich and Vetec in the highest purity available and used without further purification. Syntheses of the compounds Compounds were synthesized by modifying the existing methodology in the literature [50]. The compounds were prepared by condensation between 3,4,5-trimethoxybenzoic acid hydrazide (TMP, 1.0

A deep-red fluorophore based on naphthothiadiazole as emitter with hybridized local and charge transfer and ambipolar transporting properties for electroluminescent devices

• Suangsiri Arunlimsawat,
• Patteera Funchien,
• Pongsakorn Chasing,
• Atthapon Saenubol,
• Taweesak Sudyoadsuk and
• Vinich Promarak

Beilstein J. Org. Chem. 2023, 19, 1664–1676, doi:10.3762/bjoc.19.122

• purchased from commercial resources and used without further purification. 1H NMR and 13C NMR spectra were recorded with a Bruker AVANCE III HD 600 (600 MHz for 1H and 151 MHz for 13C) using CDCl3 as a solvent containing TMS as an internal standard. High-resolution mass spectrometry (HRMS) analysis was

• under reduced pressure. The residue was crystallized from CH2Cl2/methanol to obtain compound 3 as a mixture with unreacted starting material and dibrominated product which was used in the next step without further purification. White solid (1.34 g, 2.32 mmol). HRMS–APCI–TOF m/z: [M + H]+ calcd for

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

• adding a methanol/water mixture; thus, no lengthy purification steps were required for any of the syntheses. Yields of 52.4%, 80.2%, 58.1%, and 68.3% were obtained for PDIN-FB, PDIN-B, CN-PDIN-FB, and CN-PDIN-B, respectively. All compounds were structurally characterized using 1H NMR spectroscopy, 13C

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

• relatively low. Thermodynamics dominates the depolymerization of methacrylates [204][205]. Therefore, pyrolysis of PMMA gives a relatively high conversion to its monomer and the purification is straightforward [206][207]. Polyethylene and polypropylene make up a major fraction of commercial polymers. However

Cyclodextrins permeabilize DPPC liposome membranes: a focus on cholesterol content, cyclodextrin type, and concentration

• Ghenwa Nasr,
• Hélène Greige-Gerges,
• Sophie Fourmentin,
• Abdelhamid Elaissari and
• Nathalie Khreich

Beilstein J. Org. Chem. 2023, 19, 1570–1579, doi:10.3762/bjoc.19.115

• sulforhodamine B were purchased from Sigma-Aldrich, USA. 4-Amino-3-hydroxy-1-naphthalene sulfonic acid was purchased from Fluka, India. Sulfuric acid was purchased from ACROS Organics, Belgium and diethyl ether was purchased from VWR-Prolabo Chemicals, Belgium. Liposomes preparation, extrusion, and purification

• (Avanti Polar Lipids, Switzerland) of decreasing pore sizes resulting in a homogenous mixture of LUVs (large unilamellar vesicles). Finally, the purification of the SRB-loaded LUVs to eliminate unencapsulated SRB and lipid molecules from liposomes was carried out via a centrifugation (2 hours, 15 000 rpm

Secondary metabolites of Diaporthe cameroonensis, isolated from the Cameroonian medicinal plant Trema guineensis

• Bel Youssouf G. Mountessou,
• Élodie Gisèle M. Anoumedem,
• Blondelle M. Kemkuignou,
• Yasmina Marin-Felix,
• Frank Surup,
• Marc Stadler and
• Simeon F. Kouam

Beilstein J. Org. Chem. 2023, 19, 1555–1561, doi:10.3762/bjoc.19.112

• reversed phases (RP) were used for the purification of compounds. RP flash and p-HPLC systems (PLC 2050, Gilson, Wisconsin-USA; and Flash and prep HPLC, C-850, Büchi) were equipped with appropriate columns viz., VP Nucleodur C18 HTec (10 µm, 250 × 40 mm, Macherey-Nagel, Germany), Gemini C18 (10 µm, 250

• p-HPLC was obtained from a Milli-Q water purification system (Millipore, Schwalbach, Germany) and all organic solvents and reagents were of analytical grade. Evaporation of solvents from fractions was performed using rotary evaporators equipped with a vacuum controller and diaphragm pump vacuum (Hei

Synthesis of 5-arylidenerhodanines in L-proline-based deep eutectic solvent

• Stéphanie Hesse

Beilstein J. Org. Chem. 2023, 19, 1537–1544, doi:10.3762/bjoc.19.110

• classical organic solvents were used. The expected compounds are recovered by a simple filtration after hydrolysis and no purification is required. Those derivatives were studied for their antioxidant activities and the results are consistent with those reported in the literature indicating that phenolic

• purification steps as a real environmentally benign synthetic process should as far as possible exclude organic solvents from all stages. In a first attempt, vanillin was reacted with rhodanine for 2 h at room temperature in Pro/Gly (1:2) and product 3a was obtained in 57% yield by a simple filtration after

• (0.5 mmol) were sequentially added to the DES and the reaction mixture was stirred at 60 °C for the indicated time. Then, water (10 mL) was added at room temperature and the formed precipitate was collected by filtration and washed with 10 mL of water. No further purification was needed. (Z)-5-(5

Complexes of resorcin[4]arene with secondary amines: synthesis, solvent influence on “in-out” structure, and theoretical calculations of non-covalent interactions

• Waldemar Iwanek

Beilstein J. Org. Chem. 2023, 19, 1525–1536, doi:10.3762/bjoc.19.109

• were obtained from Sigma-Aldrich, Fluka, and Merck with purity class of 99% and were used without further purification. R[4]A (2,4,6,8-tetraisobutyl-1,3,5,7(1,3)-tetrabenzenacyclooctaphan-14,16,34,36,54,56,74,76-octaol) was synthesized according to the procedure described in the paper [32]. Calculation

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

• elution buffer used for protein purification through Ni2+-NTA affinity chromatography. While domain B alone showed a substantial enzyme precipitation after 12 h at 4 °C, full length 2MIBS did not (Figure 1B), suggesting that the A domain increases enzyme solubility and long-term stability. This effect

• (Karlsruhe, Germany) and used without purification. Solvents for column chromatography were purchased in p.a. grade and purified by distillation. Thin-layer chromatography was performed with 0.2 mm precoated plastic sheets Polygram Sil G/UV254 purchased from Machery-Nagel (Düren, Germany). Column

• ). The combined extracts were dried with MgSO4 and concentrated under reduced pressure to afford the bromide, which was used for phosphorylation without purification. (NBu4)3HP2O7 (4.02 g, 4.46 mmol, 1.5 equiv) was dissolved in acetonitrile (1 mL), and the bromide (mixed with 10 mL acetonitrile) was

One-pot nucleophilic substitution–double click reactions of biazides leading to functionalized bis(1,2,3-triazole) derivatives

• Hans-Ulrich Reissig and
• Fei Yu

Beilstein J. Org. Chem. 2023, 19, 1399–1407, doi:10.3762/bjoc.19.101

• when benzyl azide (1) and the simple alkyne 2 were combined in the presence of 0.2 equiv of copper(I) iodide in triethylamine as solvent (Scheme 2, reaction 1). After 16 hours at room temperature and chromatographic purification compound 3 was isolated in 79% yield as colorless liquid. Interestingly

Consecutive four-component synthesis of trisubstituted 3-iodoindoles by an alkynylation–cyclization–iodination–alkylation sequence

• Nadia Ledermann,
• Alae-Eddine Moubsit and
• Thomas J. J. Müller

Beilstein J. Org. Chem. 2023, 19, 1379–1385, doi:10.3762/bjoc.19.99

• isolation) accounts for an average yield of 55–90% per bond-forming step which can be considered to be relative efficient, also because only a single terminal purification step is required. However, noteworthy, the 3-iodoindoles are sensitive to light and prolonged storage at room temperature, even under

Synthesis of ether lipids: natural compounds and analogues

• Marco Antônio G. B. Gomes,
• Alicia Bauduin,
• Chloé Le Roux,
• Romain Fouinneteau,
• Wilfried Berthe,
• Mathieu Berchel,
• Hélène Couthon and
• Paul-Alain Jaffrès

Beilstein J. Org. Chem. 2023, 19, 1299–1369, doi:10.3762/bjoc.19.96

Unravelling a trichloroacetic acid-catalyzed cascade access to benzo[f]chromeno[2,3-h]quinoxalinoporphyrins

• Chandra Sekhar Tekuri,
• Pargat Singh and
• Mahendra Nath

Beilstein J. Org. Chem. 2023, 19, 1216–1224, doi:10.3762/bjoc.19.89

• . After workup and chromatographic purification, the isolated product was characterized based on spectral data analysis as copper(II) benzo[f]quinoxalinoporphyrin intermediate 17. Further, porphyrin 17 reacted with benzaldehyde and dimedone in chloroform containing 20 mol% trichloroacetic acid at 65 °C to

Two new lanostanoid glycosides isolated from a Kenyan polypore Fomitopsis carnea

• Winnie Chemutai Sum,
• Sherif S. Ebada,
• Didsanutda Gonkhom,
• Cony Decock,
• Rémy Bertrand Teponno,
• Josphat Clement Matasyoh and
• Marc Stadler

Beilstein J. Org. Chem. 2023, 19, 1161–1169, doi:10.3762/bjoc.19.84

• , Germany), and Avantor Performance Materials (Deventer, Netherlands). An in-house Purelab® flex water purification system (Veolia Water Technologies, Celle, Germany), was used in the preparation of deionized water. Fungal material examined The current study specimen was collected by one of the authors C.D

• incubation following the aforementioned established procedures to afford 0.5 g (mycelial) and 1.5 g (supernatant) ethyl acetate extracts for Q6/2 cultures and 3.44 g ethyl acetate extract for rice cultures. Isolation of compounds 1–4 Purification of the rice and Q6/2 media cultures was achieved by using a

The effect of dark states on the intersystem crossing and thermally activated delayed fluorescence of naphthalimide-phenothiazine dyads

• Liyuan Cao,
• Xi Liu,
• Xue Zhang,
• Jianzhang Zhao,
• Fabiao Yu and
• Yan Wan

Beilstein J. Org. Chem. 2023, 19, 1028–1046, doi:10.3762/bjoc.19.79

• . Experimental General methods All the chemicals used in synthesis are analytical pure and were used as received without further purification. UV–vis absorption spectra were measured on a UV-2550 Shimadzu spectrophotometer. Fluorescence spectra were recorded with an FS5 spectrofluorometer (Edinburgh instruments

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

• purification steps. Keywords: automated glycan assembly; photocleavable linker; polysaccharides; solid-phase synthesis; Introduction Automated glycan assembly (AGA) is a solid-phase method that enables the rapid synthesis of complex oligo- and polysaccharides from protected monosaccharide building blocks

• cleavage is probably influenced by glycan structure, solubility, and aggregation tendency [26]. Lastly, purification of the protected glycan upon cleavage could be affected by the presence or absence of a linker. L1 or L2 were conjugated to Merrifield resins with initial loadings of 0.5 mmol/g and 1.0 mmol

• Information File 1, section 2.3, module C). The outcome of each AGA experiment was analyzed in terms of: i) HPLC purity based on the chromatogram of the crude sample after AGA and UV cleavage, ii) isolated yield of the target compound after photocleavage and HPLC purification (path A). The syntheses of the α

Five new sesquiterpenoids from agarwood of Aquilaria sinensis

• Hong Zhou,
• Xu-Yang Li,
• Hong-Bin Fang,
• He-Zhong Jiang and
• Yong-Xian Cheng

Beilstein J. Org. Chem. 2023, 19, 998–1007, doi:10.3762/bjoc.19.75

• methods were used to purify the extract, such as MCI gel CHP 20, silica gel column, vacuum liquid chromatography, and semi-preparative HPLC purification, to obtain pure compounds. A total of ten compounds, including five new eudesmane-type sesquiterpenoids (1–5), and five known compounds were identified

Synthesis of tetrahydrofuro[3,2-c]pyridines via Pictet–Spengler reaction

• Elena Y. Mendogralo and
• Maxim G. Uchuskin

Beilstein J. Org. Chem. 2023, 19, 991–997, doi:10.3762/bjoc.19.74

• . In most cases, we observed the abundant tarring of the reaction mixture and we could not achieve the full conversion of the starting tetrahydrofuro[3,2-c]pyridine 4a in any experiment. The best results were achieved when HCl in 1,4-dioxane was used (Scheme 3). However, upon isolation and purification

Clauson–Kaas pyrrole synthesis using diverse catalysts: a transition from conventional to greener approach

• Dileep Kumar Singh and
• Rajesh Kumar

Beilstein J. Org. Chem. 2023, 19, 928–955, doi:10.3762/bjoc.19.71

• solvent and reaction time. The environmental impacts are manifold, including excessive utilization of organic solvents, high-temperature reactions, the production of hazardous byproducts, and by the use of traditional purification techniques. Therefore, green chemistry methods in Clauson–Kaas synthesis

First synthesis of acylated nitrocyclopropanes

• Kento Iwai,
• Rikiya Kamidate,
• Khimiya Wada,
• Haruyasu Asahara and
• Nagatoshi Nishiwaki

Beilstein J. Org. Chem. 2023, 19, 892–900, doi:10.3762/bjoc.19.67

• our study using ethyl acetoacetate (3c) as starting 1,3-dicarbonyl compound according to method b (Scheme 2). After heating an acetonitrile solution of 3c, N-bromosuccinimide, and p-toluenesulfonic acid [7], α-bromoacetoacetate 6c was isolated with a 44% yield after purification of the reaction

• researchers studying organic syntheses using functionalized cyclopropanes. Experimental General All reagents were purchased from commercial sources and used without further purification. 1H and13C NMR spectra were recorded on Bruker DPX-400 and JEOL JMN-ECZ400S spectrometers (400 MHz and 100 MHz, respectively

Asymmetric tandem conjugate addition and reaction with carbocations on acylimidazole Michael acceptors

• Brigita Mudráková,
• Renata Marcia de Figueiredo,
• Jean-Marc Campagne and
• Radovan Šebesta

Beilstein J. Org. Chem. 2023, 19, 881–888, doi:10.3762/bjoc.19.65

• charges at C-2 of enolates cannot account for the differences in the yields of the trapping products as these are affected by their specific stabilities and issues during isolation and purification. As an additional question that we tried to answer with these calculations was the comparison of the Zn