Hydrogen-bond activation enables aziridination of unactivated olefins with simple iminoiodinanes

• Phong Thai,
• Lauv Patel,
• Diyasha Manna and
• David C. Powers

Beilstein J. Org. Chem. 2024, 20, 2305–2312, doi:10.3762/bjoc.20.197

• (denoted by asterisk *) of HFIP in the presence of iminoiodinane 2c suggesting hydrogen bonding observed in 1H NMR spectra (CD3CN) of: 8.0 mM 2c with no HFIP (blue line), 8.0 mM 2c with 32 mM HFIP (green line), 4.0 mM of 4-(trifluoromethyl)benzenesulfonamide with 32 mM HFIP (purple line), only 32 mM HFIP

Deuterated reagents in multicomponent reactions to afford deuterium-labeled products

• Kevin Schofield,
• Shayna Maddern,
• Yueteng Zhang,
• Grace E. Mastin,
• Rachel Knight,
• Wei Wang,
• James Galligan and
• Christopher Hulme

Beilstein J. Org. Chem. 2024, 20, 2270–2279, doi:10.3762/bjoc.20.195

• . Optimization of deuterated Leuckart–Wallach reactiona. Microsomal stability package of deuterated and non-deuterated dihydropyridines. Supporting Information Supporting Information File 86: Experimental and analytical data and copies of NMR spectra. Acknowledgements We thank the UA mass spectrometry and NMR

Metal-free double azide addition to strained alkynes of an octadehydrodibenzo[12]annulene derivative with electron-withdrawing substituents

• Naoki Takeda,
• Shuichi Akasaka,
• Susumu Kawauchi and
• Tsuyoshi Michinobu

Beilstein J. Org. Chem. 2024, 20, 2234–2241, doi:10.3762/bjoc.20.191

• indicates that the formed double azide adduct is 6a, which is consistent with our previous report [18]. The double azide addition was further investigated by changing the reaction temperature. The rate constant was determined by the temperature-dependent 1H NMR spectra in CDCl3. The reaction kinetics

• partially azidated poly(vinyl chloride) (PVA-N3) was prepared by stirring poly(vinyl chloride) and NaN3 in DMF at room temperature overnight. Measurements NMR spectra were recorded using a JEOL mode Al300 (300 MHz) at room temperature. Deuterated chloroform was used as the solvent unless otherwise stated

Selective hydrolysis of α-oxo ketene N,S-acetals in water: switchable aqueous synthesis of β-keto thioesters and β-keto amides

• Haifeng Yu,
• Wanting Zhang,
• Xuejing Cui,
• Zida Liu,
• Xifu Zhang and
• Xiaobo Zhao

Beilstein J. Org. Chem. 2024, 20, 2225–2233, doi:10.3762/bjoc.20.190

• thioesters and β-keto amides by simply changing reaction conditions. These features, including a good substrate scope, excellent yield and selectivity and ease of scale-up, rendered the green hydrolysis reaction very environment-friendly, practical, and attractive. Experimental 1H and 13C{1H} NMR spectra

• ]. Supporting Information Supporting Information File 68: Analytic data and copies of 1H and 13C NMR spectra of compounds 2 and 3. Funding We are grateful to Funds for the Natural Science Foundation of Jilin Province, China (20240101156JC, 20210101128JC) and the Program for Innovative Research Team of Baicheng

Heterocycle-guided synthesis of m-hetarylanilines via three-component benzannulation

• Andrey R. Galeev,
• Maksim V. Dmitriev,
• Alexander S. Novikov and
• Andrey N. Maslivets

Beilstein J. Org. Chem. 2024, 20, 2208–2216, doi:10.3762/bjoc.20.188

• data of new compounds and NMR spectra. Supporting Information File 64: xyz files with Cartesian atomic coordinates for all model structures and CIF-files for compounds 1g, 3ab, 3bb and 3ca. Funding This study was performed under financial support of the Ministry of Science and Higher Education of the

Natural resorcylic lactones derived from alternariol

• Joachim Podlech

Beilstein J. Org. Chem. 2024, 20, 2171–2207, doi:10.3762/bjoc.20.187

• : Total synthesis and comparison of the NMR spectra revealed that this natural product is identical with altertenuol [41], whose structure was correctly given previously [42]. Furthermore, the originally proposed structures [43] of graphislactones E and F were corrected after total synthesis and

• comparison of NMR spectra [44]. Occasionally, natural products have been reported more than one time as new compounds and were given several names. Only the first given name should be used and further names are thus obsolete: Verrulactone D is erroneously given in the SciFinder database as synonym for

• synthesis [186] and comparison of the NMR spectra of synthesized material and of an original sample which survived from the 1950ies (Figure 10) [41]. This study further confirmed that a natural product altenuisol, whose structure 31a was proposed based on 1H NMR-spectroscopic methods, had been assigned

O,S,Se-containing Biginelli products based on cyclic β-ketosulfone and their postfunctionalization

• Kateryna V. Dil and
• Vitalii A. Palchykov

Beilstein J. Org. Chem. 2024, 20, 2143–2151, doi:10.3762/bjoc.20.184

• ]. We hope that compound 2r and its analogues obtained in this work can be further deeply studied by in silico and in vitro methods to discover the compound most suitable for clinical trials. The structures of the synthesized compounds 2a–r were confirmed by spectral data. The 1H NMR spectra of the

• signals clearly corresponds to the heterocycles depicted above. Figure S8 (see Supporting Information File 1) shows 1H NMR spectra for Ph-substituted O,S,Se-DHPMs 2a,h,o. It can be seen from them that when going from oxygen to selenium (2h→2a→2o), the signals of both NH groups shift to down field (7.87

• /9.26→9.75/10.50→10.26/10.85 ppm) and become more equivalent (Δδ = 1.39→0.75→0.59 ppm accordingly). The key signal in the 13C NMR spectra is located in the regions 174.04–174.69 ppm (C=S), 151.44–151.86 ppm (C=O), and 170.15–170.91 ppm (C=Se) accordingly. Utilization of reaction products The Biginelli

From perfluoroalkyl aryl sulfoxides to ortho thioethers

• Yang Li,
• Guillaume Dagousset,
• Emmanuel Magnier and
• Bruce Pégot

Beilstein J. Org. Chem. 2024, 20, 2108–2113, doi:10.3762/bjoc.20.181

• . The scope of aryl perfluoromethyl sulfoxides and a selenoxide. The scope of alkyl nitriles. Optimization of the reaction conditions. Supporting Information Supporting Information File 48: Experimental procedures, characterization data of all isolated products as well as copies of NMR spectra for

Computational toolbox for the analysis of protein–glycan interactions

• Ferran Nieto-Fabregat,
• Maria Pia Lenza,
• Angela Marseglia,
• Cristina Di Carluccio,
• Antonio Molinaro,
• Alba Silipo and
• Roberta Marchetti

Beilstein J. Org. Chem. 2024, 20, 2084–2107, doi:10.3762/bjoc.20.180

Diastereoselective synthesis of highly substituted cyclohexanones and tetrahydrochromene-4-ones via conjugate addition of curcumins to arylidenemalonates

• Deepa Nair,
• Abhishek Tiwari,
• Banamali Laha and
• Irishi N. N. Namboothiri

Beilstein J. Org. Chem. 2024, 20, 2016–2023, doi:10.3762/bjoc.20.177

• . Reaction optimisation using phase-transfer catalysts.a Scope of alkylidenemalonates and curcumins.a Supporting Information Supporting Information File 38: Experimental procedures and characterization data. Supporting Information File 39: Copies of NMR spectra of all new compounds. Supporting Information

Allostreptopyrroles A–E, β-alkylpyrrole derivatives from an actinomycete Allostreptomyces sp. RD068384

• Marwa Elsbaey,
• Naoya Oku,
• Mohamed S. A. Abdel-Mottaleb and
• Yasuhiro Igarashi

Beilstein J. Org. Chem. 2024, 20, 1981–1987, doi:10.3762/bjoc.20.174

• HRESITOFMS and NMR analytical data (Table 2), inferring that compounds 2 and 3 were isomers of 1. In fact, their NMR spectra were closely similar to those for 1 except a little difference in the alkyl side chain terminus. In a COSY spectrum of 2, the terminal doublet methyl proton was correlated with an

• -configurations were proposed for compounds 2 and 3. However, this prediction was not confirmed by chemical derivatization due to their limited availability. 1H and 13C NMR spectra of compounds 4 and 5 were superimposable to those of 1 except for methylene resonances, supporting that both 4 and 5 possess the same

Development of a flow photochemical process for a π-Lewis acidic metal-catalyzed cyclization/radical addition sequence: in situ-generated 2-benzopyrylium as photoredox catalyst and reactive intermediate

• Masahiro Terada,
• Zen Iwasaki,
• Ryohei Yazaki,
• Shigenobu Umemiya and
• Jun Kikuchi

Beilstein J. Org. Chem. 2024, 20, 1973–1980, doi:10.3762/bjoc.20.173

• , experimental procedures, and characterization data. Supporting Information File 30: Copies of NMR spectra. Funding This work was partially supported by a Grant-in-Aid for Scientific Research on Innovative Areas “Hybrid Catalysis for Enabling Molecular Synthesis on Demand” (JP17H06447) and a Grant-in-Aid for

1,2-Difluoroethylene (HFO-1132): synthesis and chemistry

• Liubov V. Sokolenko,
• Taras M. Sokolenko and
• Yurii L. Yagupolskii

Beilstein J. Org. Chem. 2024, 20, 1955–1966, doi:10.3762/bjoc.20.171

• ]. Additionally, when the reaction was performed using DMSO-d6 (or CD3CN) and CH3ONa, H/D exchange occurred already at ambient temperature (25 °C, 20 h) [78]. The formation of CDF=CDF was confirmed by NMR spectroscopy, namely by the change of signal multiplicity in the 19F NMR spectra of E- and Z-isomers of 1,2

• -difluoroethylene and the disappearance of vinyl protons resonances in the 1H NMR spectra [78]. Addition to the C=C bond Halogen addition: 1,2-Difluoroethylene was reported to react with chlorine [46][79] and bromine [51] under irradiation, yielding 1,2-difluoro-1,2-dihaloethanes in moderate to high yield (Scheme 9

Regioselective alkylation of a versatile indazole: Electrophile scope and mechanistic insights from density functional theory calculations

• Pengcheng Lu,
• Luis Juarez,
• Paul A. Wiget,
• Weihe Zhang,
• Krishnan Raman and
• Pravin L. Kotian

Beilstein J. Org. Chem. 2024, 20, 1940–1954, doi:10.3762/bjoc.20.170

• moisture-sensitive reagents were performed under a nitrogen or argon atmosphere. Silica gel chromatography was performed using prepacked silica gel columns (RediSep® Rf, Teledyne ISCO). An aluminum block atop a hotplate with a thermocouple was used to heat reactions to the specified temperatures. NMR

• spectra were acquired on Bruker 300 MHz spectrometers equipped with 5 mm BBFO probes. HRMS data were acquired using an Agilent 6530 LC/Q-TOF using a Dual AJS/ESI ion source, and the isotope 79 was used for HRMS analysis for any bromine-containing compounds. Synthesis All procedures and spectra can be

A new platform for the synthesis of diketopyrrolopyrrole derivatives via nucleophilic aromatic substitution reactions

• Vitor A. S. Almodovar and
• Augusto C. Tomé

Beilstein J. Org. Chem. 2024, 20, 1933–1939, doi:10.3762/bjoc.20.169

• than the oxygen due to the preferential existence of 4-hydroxypyridine in the pyridin-4-one tautomeric form [37][38][39]. The structures of dyes 3a–f, 4a, 4d and 4f were unambiguously established through their 1H, 13C and 19F NMR and mass spectra. The 1H NMR spectra of the symmetrical compounds

• the protons of the N–CH2C6F5 and N–CH2C6F4XR groups, respectively. All 19F NMR spectra confirmed the selective substitution of the 4-fluorine atoms (in one or in two rings) by the disappearance of the signal corresponding to the resonance of those atoms. Mass spectra of compounds 3a–f, 4a, 4d and 4f

• apparatus. NMR spectra were recorded on a Bruker DRX 300 Avance operating at 300.13 MHz (for 1H NMR), at 75.47 MHz (for 13C NMR) and 282 MHz (for 19F NMR). Deuterated chloroform (CDCl3) was used as the solvent and tetramethylsilane (TMS) as the internal reference. The chemical shifts (δ) are expressed in

Negishi-coupling-enabled synthesis of α-heteroaryl-α-amino acid building blocks for DNA-encoded chemical library applications

• Matteo Gasparetto,
• Balázs Fődi and
• Gellért Sipos

Beilstein J. Org. Chem. 2024, 20, 1922–1932, doi:10.3762/bjoc.20.168

• each reaction (Supporting Information File 1). Supporting Information Supporting Information File 14: Experimental part and NMR spectra. Acknowledgements The authors thank Dr. Attila Sveiczer and Dr. Mounir Raji for the consultations and technical support during the practical work of the project, and

Electrochemical radical cation aza-Wacker cyclizations

• Sota Adachi and
• Yohei Okada

Beilstein J. Org. Chem. 2024, 20, 1900–1905, doi:10.3762/bjoc.20.165

• cyclization.a Supporting Information Supporting Information File 6: General remarks and characterization data, including copies of 1H and 13C NMR spectra. Funding This work was supported in part by JSPS KAKENHI Grant No. 22K05450 (to Y. O.), and TEPCO Memorial Foundation (to Y. O.).

Access to 2-oxoazetidine-3-carboxylic acid derivatives via thermal microwave-assisted Wolff rearrangement of 3-diazotetramic acids in the presence of nucleophiles

• Ivan Lyutin,
• Vasilisa Krivovicheva,
• Grigory Kantin and
• Dmitry Dar’in

Beilstein J. Org. Chem. 2024, 20, 1894–1899, doi:10.3762/bjoc.20.164

• information, X-ray crystallographic data, synthetic procedures, analytical data and NMR spectra for the reported compounds. Acknowledgements We thank the Research Center for Magnetic Resonance, the Center for Chemical Analysis and Materials Research, and the Center for X-ray Diffraction Methods of Saint

A facile three-component route to powerful 5-aryldeazaalloxazine photocatalysts

• Ivana Weisheitelová,
• Radek Cibulka,
• Marek Sikorski and
• Tetiana Pavlovska

Beilstein J. Org. Chem. 2024, 20, 1831–1838, doi:10.3762/bjoc.20.161

• -aryldeazaalloxazines in any case. Finally, the unsubstituted derivative 2x was formed with a yield of only 15% using DMF/AlCl3. The isolated products 2a–x were characterized by 1H, 13C NMR and mass-spectral methods. The 1H NMR spectra of 5-aryldeazaalloxazines 2a–x, along with protons of aryl substituents of aldehyde

• moiety and pyrimido[4,5-b]quinoline core, contained singlets with 3H intensity of the N(1)–CH3 and N(3)–CH3 groups of the barbituric acid fragment at 3.20–3.56 ppm. The 13C NMR spectra of 5-aryldeazaalloxazines 2a–x were represented by groups of singlets at 27.9–57.2 and 100.0–160.5 ppm. The

• named using ChemDraw. Nuclear magnetic resonance (NMR) spectra were recorded on an Agilent 400-MR DDR2 (399.94 MHz for 1H, 100.58 MHz for 13C, 376.50 MHz for 19F) or on a JNM-ECZ500R NMR spectrometer, JEOL Resonance, (500.16 MHz for 1H, 125.77 MHz for 13C, 470.60 MHz for 19F) at 298 K unless otherwise

Chiral bifunctional sulfide-catalyzed enantioselective bromolactonizations of α- and β-substituted 5-hexenoic acids

• Sao Sumida,
• Ken Okuno,
• Taiki Mori,
• Yasuaki Furuya and
• Seiji Shirakawa

Beilstein J. Org. Chem. 2024, 20, 1794–1799, doi:10.3762/bjoc.20.158

• and solvents. Substrate scope. Larger-scale synthesis and transformations of bromolactonization product 3a. Supporting Information Supporting Information File 20: Experimental procedures, characterization data, copies of NMR spectra, and copies of HPLC charts. Funding K.O. thanks the JSPS for a

Oxidative fluorination with Selectfluor: A convenient procedure for preparing hypervalent iodine(V) fluorides

• Samuel M. G. Dearman,
• Xiang Li,
• Yang Li,
• Kuldip Singh and
• Alison M. Stuart

Beilstein J. Org. Chem. 2024, 20, 1785–1793, doi:10.3762/bjoc.20.157

• deposition numbers CCDC: 2351949 and 2351950. Supporting Information File 18: Experimental procedures, characterisation data, DFT calculations and 1H, 13C and 19F NMR spectra and crystallographic data. Funding SMGD and AMS thank the School of Chemistry, University of Leicester, for their generous support

Ugi bisamides based on pyrrolyl-β-chlorovinylaldehyde and their unusual transformations

• Alexander V. Tsygankov,
• Vladyslav O. Vereshchak,
• Tetiana O. Savluk,
• Serhiy M. Desenko,
• Valeriia V. Ananieva,
• Oleksandr V. Buravov,
• Yana I. Sakhno,
• Svitlana V. Shishkina and
• Valentyn A. Chebanov

Beilstein J. Org. Chem. 2024, 20, 1773–1784, doi:10.3762/bjoc.20.156

• stirring for three hours (Scheme 3, conditions A). However, the results of this attempted post-Ugi transformation were quite unexpected: Instead of acid 11, we isolated the amide of the unsaturated derivative of pyruvic acid 10a according to the 1H and 13C NMR spectra and mass spectrometry data. In order

• conventional thermal heating, amide 10a was isolated, albeit in a lower yield and accompanied with tar formation. In addition to the 1H, 13C NMR spectra and mass spectrometry data, the structure of compound 10d was established by X-ray diffraction analysis (Figure 3). It was also found that the substituents at

• of p-CF3-substituted aniline when synthesizing bisamide 6d. The yield of the amide 10c was about 8% and it was also the first to precipitate. In addition, it is worth mentioning that the corresponding amides 10 were observed in 1H NMR spectra and LC–MS analysis in many mother liquors after filtration

Harnessing unprotected deactivated amines and arylglyoxals in the Ugi reaction for the synthesis of fused complex nitrogen heterocycles

• Javier Gómez-Ayuso,
• Pablo Pertejo,
• Tomás Hermosilla,
• Israel Carreira-Barral,
• Roberto Quesada and
• María García-Valverde

Beilstein J. Org. Chem. 2024, 20, 1758–1766, doi:10.3762/bjoc.20.154

• explained by the intramolecular hydrogen bond formed between the hydroxy group and the carbamide substituent, which explains the high deshielding observed in the 1H NMR spectra for the signal of the OH group (around 8.5 ppm). As before, we also explored the stereochemical outcome in the synthesis of

Oxidation of benzylic alcohols to carbonyls using N-heterocyclic stabilized λ³-iodanes

• Thomas J. Kuczmera,
• Pim Puylaert and
• Boris J. Nachtsheim

Beilstein J. Org. Chem. 2024, 20, 1677–1683, doi:10.3762/bjoc.20.149

• coordination of the triflate to two positions of the iodane. Thermal ellipsoids are displayed with 50% probability. Selected bond lengths and angles: I1–N1: 2.44(4) Å; I1–O1: 1.94(9) Å; I1–O2: 3.04(1) Å; C1–I1–N1: 73.5(8)°; O1–I1–N1: 166.6(5)°; N1–I1–C1–O1: 177.8(3)°. 1H NMR spectra of the time-dependent

• NHI 1c (10.0 µmol) and alcohol (2 or 3a, 10.0 µmol) were dissolved in CD3CN (600 µL) and 1H NMR spectra were recorded. Oxidation of 3a to 4a using different iodine(III) reagents with AlCl3 as an additive. Conditions: The turnover of an equimolar mixture of 3a, iodine(III), and AlCl3 (10.0 µmol

Ring opening of photogenerated azetidinols as a strategy for the synthesis of aminodioxolanes

• Henning Maag,
• Daniel J. Lemcke and
• Johannes M. Wahl

Beilstein J. Org. Chem. 2024, 20, 1671–1676, doi:10.3762/bjoc.20.148

• acids. Comparison of the effect of structural variations on the photoreaction. Supporting Information Supporting Information File 2: Experimental procedures, characterization data and copies of NMR spectra. Acknowledgements Generous support from the Johannes Gutenberg-Universität Mainz is acknowledged