HPW-Catalyzed environmentally benign approach to imidazo[1,2-a]pyridines

• Luan A. Martinho and
• Carlos Kleber Z. Andrade

Beilstein J. Org. Chem. 2024, 20, 628–637, doi:10.3762/bjoc.20.55

• reproducible. Unsuccessful substrates for these reactions were also detected (Scheme 4). The use of 2-amino-3-hydroxypyridine provided a complex mixture of products (1H and 13C NMR analysis). When 6-amino-2-thiouracil was used, only the starting materials were recovered. Regarding the aldehyde component, the

Chemical and biosynthetic potential of Penicillium shentong XL-F41

• Ran Zou,
• Xin Li,
• Xiaochen Chen,
• Yue-Wei Guo and
• Baofu Xu

Beilstein J. Org. Chem. 2024, 20, 597–606, doi:10.3762/bjoc.20.52

• m/z 341.1862 [M − H]− (calcd for C20H25N2O3, 341.1870). Spectroscopic analysis, including 1H NMR, 13C NMR (Table 1), and DEPT, revealed that compound 1 contains three methyl groups, one of which is oxygenated, four methines, three saturated non-protonated carbons, and two ketone carbonyl carbons (δC

• substructure at C-14 with a methine at C-16, indicated by the methoxy group. The position of the methoxy substituent was established by HMBC correlations, and the 13C NMR data suggested that compound 1 includes a 4-oxo-2,3-dihydro-(1H)-quinolin-3-yl fragment. The planar structure was established from HMBC

• 335.1719 [M + Na]+ (calcd for C19H24N2O2Na+, 335.1730) and m/z 311.1755 [M − H]− (calcd for C19H23N2O2, 311.1765). Spectroscopic analysis using 1H NMR, 13C NMR, and DEPT (Table 2) indicated that compound 2 comprises two methyl groups, five methines, five saturated non-protonated carbons, and one ketone

Synthesis of photo- and ionochromic N-acylated 2-(aminomethylene)benzo[b]thiophene-3(2Н)-ones with a terminal phenanthroline group

• Vladimir P. Rybalkin,
• Sofiya Yu. Zmeeva,
• Lidiya L. Popova,
• Irina V. Dubonosova,
• Olga Yu. Karlutova,
• Oleg P. Demidov,
• Alexander D. Dubonosov and
• Vladimir A. Bren

Beilstein J. Org. Chem. 2024, 20, 552–560, doi:10.3762/bjoc.20.47

• were isolated preparatively and fully characterized by IR, 1H, and 13C NMR spectroscopy as well as HRMS and XRD methods. The reverse thermal reaction was catalyzed by protonic acids. N-Acylated compounds exclusively with Fe2+ formed nonfluorescent complexes with a contrast naked-eye effect: a color

• products 3a–c were comprehensively characterized by IR, 1Н and 13C NMR spectroscopy, HRMS (Supporting Information File 2) as well as by X-ray diffraction analysis. The molecular structure of 3b is shown in Figure 3. The crystal data, details of the data collection and refinements for 3b as well as complete

• reaction occurred catalytically in the presence of HClO4. A special technique for the preparative synthesis of photoproducts was developed. For the first time in the course of studying N→O acylotropic migrations, O-acylated photoproducts were comprehensively characterized by IR, 1H and 13C NMR spectroscopy

Synthesis and biological profile of 2,3-dihydro[1,3]thiazolo[4,5-b]pyridines, a novel class of acyl-ACP thioesterase inhibitors

• Jens Frackenpohl,
• David M. Barber,
• Guido Bojack,
• Birgit Bollenbach-Wahl,
• Ralf Braun,
• Rahel Getachew,
• Sabine Hohmann,
• Kwang-Yoon Ko,
• Karoline Kurowski,
• Bernd Laber,
• Rebecca L. Mattison,
• Thomas Müller,
• Anna M. Reingruber,
• Dirk Schmutzler and
• Andrea Svejda

Beilstein J. Org. Chem. 2024, 20, 540–551, doi:10.3762/bjoc.20.46

• ) to afford 6-bromo-5-(2-fluorophenyl)-2,3-dihydro[1,3]thiazolo[4,5-b]pyridine (13b, 596 mg, 59%). 1H NMR (600 MHz, CDCl3, δ) 4.56 (s, 2H), 6.88 (br s, 1H), 7.11–7.16 (m, 1H), 7.21 (td, J = 7.5; 1.1 Hz, 1H), 7.31 (s, 1H), 7.34 (td, J = 7.4; 1.9 Hz, 1H), 7.36–7.41 (m, 1H); 13C NMR (151 MHz, CDCl3, δ

• ), 7.07 (s, 1H), 7.09–7.12 (m, 1H), 7.19–7.21 (m, 1H), 7.32–7.36 (m, 2H); 13C NMR (151 MHz, CDCl3, δ) 17.96 (CH3), 17.99 (CH3), 48.8 (CH2), 115.6 (CH), 115.7 (CH), 121.0 (C), 121.8 (C), 124.15 (CH), 124.18 (CH), 129.59 (CH), 129.64 (CH), 130.2 (CH), 131.40 (CH), 131.43 (CH), 145.6 (C), 158.9 (C), 159.2 (C

• (m, 2H); 13C NMR (151 MHz, CDCl3, δ) 18.41 (CH3), 18.44 (CH3), 24.7 (CH3), 49.3 (CH2), 115.7 (CH), 115.8 (CH), 124.09 (CH), 124.12 (CH), 125.2 (C), 127.8 (C), 129.9 (CH), 130.0 (CH), 131.37 (CH), 131.40 (CH), 132.1 (CH), 147.0 (C), 149.6 (C), 158.9 (C), 160.6 (C), 170.6 (C); HRESIMS (m/z): [M + H

A new analog of dihydroxybenzoic acid from Saccharopolyspora sp. KR21-0001

• Rattiya Janthanom,
• Yuta Kikuchi,
• Hiroki Kanto,
• Tomoyasu Hirose,
• Arisu Tahara,
• Takahiro Ishii,
• Arinthip Thamchaipenet and
• Yuki Inahashi

Beilstein J. Org. Chem. 2024, 20, 497–503, doi:10.3762/bjoc.20.44

• determined as C12H13NO7S (requiring seven degrees of unsaturation) from the [M + H]+ ion at m/z 316.0484 (calcd. for C12H14NO7S, 316.0485) by HRESIMS. The 1H and 13C NMR spectral data of 1 are listed in Table 1. The 1H NMR and heteronuclear single quantum coherence (HSQC) data indicated the presence of two

• sp2 methines, one sp3 methine, one sp3 methylene, and one methyl group. The 13C NMR data showed the resonances of twelve carbons, which were classified into six olefinic carbons (including two oxygenated carbons: δC 151.0 and 145.2), three carbonyl carbons, one sp3 methine carbon, one sp3 methylene

• of 0.5 mL·min−1 and gradient elution with MeOH/H2O with 0.1% FA. Structure elucidation Spectra from 1H NMR at 500 MHz and 13C NMR at 125 MHz were measured in CD3OD using a JNM-ECA500 (JEOL Ltd., Tokyo Japan). Chemical shifts were referenced to CD3OD (3.31 ppm) in the 1H NMR spectra and CD3OD (49.0

Pseudallenes A and B, new sulfur-containing ovalicin sesquiterpenoid derivatives with antimicrobial activity from the deep-sea cold seep sediment-derived fungus Pseudallescheria boydii CS-793

• Zhen Ying,
• Xiao-Ming Li,
• Sui-Qun Yang,
• Hong-Lei Li,
• Xin Li,
• Bin-Gui Wang and
• Ling-Hong Meng

Beilstein J. Org. Chem. 2024, 20, 470–478, doi:10.3762/bjoc.20.42

• )], four aliphatic methylenes, four methines (with two oxygenated and one olefinic), and four exchangeable protons. The 13C NMR spectroscopic data (Table 1) displayed all 16 resonances which were classified by DEPT experiments into the categories of four methyls (including one methoxy), four methylenes

• should be mentioned that compound 3 was the first sulfur-containing ovalicin sesquiterpenoid, which was previously isolated from Sporothrix sp. FO-4649, but its absolute configuration was not explicitly represented, and their 1H and 13C NMR data were incomplete [10]. Thus, a full assignment of the NMR

• –6.10). Then, compound 2 (13.7 mg) was isolated by CC on Si gel (CH2Cl2/MeOH, 250:1 to 50:1) and preparative TLC (plate: 20 × 20 cm, developing solvent: ether/acetone 2:1) from Fr. 6.3 (578 mg). Pseudallene A (1): colorless crystals (MeOH); mp 115–117 °C; [α]D25 +20.0 (c 0.4, MeOH); 1H and 13C NMR data

(E,Z)-1,1,1,4,4,4-Hexafluorobut-2-enes: hydrofluoroolefins halogenation/dehydrohalogenation cascade to reach new fluorinated allene

• Nataliia V. Kirij,
• Andrey A. Filatov,
• Yurii L. Yagupolskii,
• Sheng Peng and
• Lee Sprague

Beilstein J. Org. Chem. 2024, 20, 452–459, doi:10.3762/bjoc.20.40

• of stereoisomers in 2:1 ratio. After isolation by distillation, 2,3-dibromo-1,1,1,4,4,4-hexafluorobutane (2) was characterized by 1H, 19F, 13C NMR and mass spectra. We studied the reaction of dibromoalkane 2 with various bases such as DBU, Hünig’s base (iPr2NEt), and potassium hydroxide (Table 1). In

• obtained by us fully correspond to the literature data [19][20]. The 1H and 19F NMR spectra of compounds 7a,b also corresponded to the data given in the literature [21][22]. We present here the spectral data for isomer 6a, as well as the missing data of 13C NMR spectra for iodoolefins 7a,b. It should be

• 11 had an allene structure. It was also important to note that the reaction proceeded more selectively in ether, which significantly reduced the amount of byproducts. Pure final alcohol 10 was isolated by column chromatography on SiO2 in 46% yield and 1H, 19F and 13C NMR spectra were in full

Mono or double Pd-catalyzed C–H bond functionalization for the annulative π-extension of 1,8-dibromonaphthalene: a one pot access to fluoranthene derivatives

• Nahed Ketata,
• Linhao Liu,
• Ridha Ben Salem and
• Henri Doucet

Beilstein J. Org. Chem. 2024, 20, 427–435, doi:10.3762/bjoc.20.37

• from Acros. KOPiv (95%) was purchased from Doug Discovery. These compounds were not purified before use. All reagents were weighed and handled in air. All reactions were carried out under an inert atmosphere with standard Schlenk techniques. 1H, 19F and 13C NMR spectra were recorded on Bruker Avance

• data of synthesized compounds. Supporting Information File 44: Copies of 1H, 19F, and 13C NMR spectra. Acknowledgements We are grateful to Dr. Elsa Caytan for NMR experiments. Part of this work has been performed using the PRISM core facility (Biogenouest, Univ Rennes, Univ Angers, INRAE, CNRS, FRANCE

Spatial arrangements of cyclodextrin host–guest complexes in solution studied by ¹³C NMR and molecular modelling

• Konstantin Lebedinskiy,
• Ivan Barvík,
• Zdeněk Tošner,
• Ivana Císařová,
• Jindřich Jindřich and
• Radim Hrdina

Beilstein J. Org. Chem. 2024, 20, 331–335, doi:10.3762/bjoc.20.33

• 2026/5, 121 16 Praha, Czech Republic Department of Inorganic Chemistry, Faculty of Science, Charles University, Hlavova 8, 128 43 Praha, Czech Republic 10.3762/bjoc.20.33 Abstract 13C NMR spectroscopic analyses of Cs symmetric guest molecules in the cyclodextrin host cavity, combined with molecular

• signals in 13C NMR spectra. This signal split can be correlated to the distance of the guest atoms from the wall of the host cavity and to the spatial separation of binding sites preferred by pairs of prochiral carbon atoms. These measurements complement traditional solid-state analyses, which rely on the

• crystallization of host–guest complexes and their crystallographic analysis. Keywords: anisotropy; 13C NMR; cyclodextrin; host–guest complexes; Introduction Complexation of organic and inorganic compounds with α-, β-, or γ-cyclodextrins and their derivatives [1] is an established tool used in medicine for drug

Discovery of unguisin J, a new cyclic peptide from Aspergillus heteromorphus CBS 117.55, and phylogeny-based bioinformatic analysis of UngA NRPS domains

• Sharmila Neupane,
• Marcelo Rodrigues de Amorim and
• Elizabeth Skellam

Beilstein J. Org. Chem. 2024, 20, 321–330, doi:10.3762/bjoc.20.32

• compound 1 was elucidated by 1D and 2D NMR and HRESIMS/MS. Unguisin B was identified by the 1H and 13C NMR data with the reported data [1][5]. Compound 1 was obtained as a white amorphous solid optically active, with +23.4 (c 0.1, MeOH). Its molecular formula was established as C41H56N8O7 by HRMS ([M + H

• . The 1H and 13C NMR spectra of 1 revealed the presence of seven amide NH signals between δH 7.43 and 8.44 ppm supported by the amide carbonyl signals at δC 173.1, 172.6, 172.6, 172.1, 172.1, 171.1 and 171.0 ppm (Table 1). An additional NH signal at δH 10.82 ppm and four aromatic signals at δH 7.50

• powder, +37 (c 0.1, EtOH) [lit +40 (c 1.0, EtOH)] [5]; for the 1H and 13C NMR spectroscopic data, see Table S2 in Supporting Information File 1. By comparison with literature data this compound was identified as unguisin B (2) [1][5], further corroborating the identification of the new unguisin J (1

Synthesis of spiropyridazine-benzosultams by the [4 + 2] annulation reaction of 3-substituted benzoisothiazole 1,1-dioxides with 1,2-diaza-1,3-dienes

• Wenqing Hao,
• Long Wang,
• Jinlei Zhang,
• Dawei Teng and
• Guorui Cao

Beilstein J. Org. Chem. 2024, 20, 280–286, doi:10.3762/bjoc.20.29

• investigated the performance of other organic and inorganic bases, but they did not improve the yield (Table 1, entries 8–12). The structure of spiropyridazine-benzosultam 3aa was determined by 1H NMR, 13C NMR, HRMS analysis and single-crystal X-ray crystallography [33]. Further experiments conducted with

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

• = 8 Hz, Ar, 1H), 6.79–6.83 (t, J = 8 Hz, Ar, 1H), 6.85–6.87 (d, J = 8 Hz, Ar, 1H), 7.09–7.13 (m, Ar, 3H), 7.49–7.51 (d, J = 8 Hz, Ar, 1H); 13C NMR (CDCl3, 100 MHz) δ 110.42, 114.41, 116.47, 119.48, 119.70, 127.00, 127.04, 128.39, 132.62, 142.45, 143.03; HRESIMS (m/z): [M + H+] calcd for C12H11BrN2

• °C; 1H NMR (DMSO-d6, 400 MHz) δ 6.87–7.00 (m, Ar, 6H), 7.31–7.35 (t, J = 8 Hz, Ar, 1H), 7.66–7.68 (d, J = 8 Hz, Ar,1H), 7.84 (s, Ar, 1H), 9.85 (s, Ar, 1H); 13C NMR (CDCl3, 100 MHz) δ 119.52, 120.23, 121.17, 121.73, 123.24, 123.40, 124.95, 130.29, 132.56, 133.67, 140.43, 150.92, 168.40; ESIMS (m/z

Comparison of glycosyl donors: a supramer approach

• Anna V. Orlova,
• Nelly N. Malysheva,
• Maria V. Panova,
• Nikita M. Podvalnyy,
• Michael G. Medvedev and
• Leonid O. Kononov

Beilstein J. Org. Chem. 2024, 20, 181–192, doi:10.3762/bjoc.20.18

• = 11.7, J4,5 = 10.3, J4,3e = 4.8, 1H, H-4), 7.27 (d, JNH,5 = 9.9, 1H, NH), 7.33–7.49 (m, 5H, Ph); 13C NMR (75 MHz, CDCl3, δ, ppm, J, Hz) 37.0 (C-3), 40.1 (CH2Cl), 40.3 (CH2Cl), 49.8 (C-5), 53.1 (OMe), 62.5 (C-9), 70.1 (C-4), 71.5, 71.8 (C-6, C-7), 75.5 (C-8), 88.2 (C-2), 114.1 (q, JC,F = 285, CF3), 114.2

• ); 13C NMR (75 MHz, CDCl3, δ, ppm, J, Hz) 25.0 (Me), 26.2 (Me), 37.7 (C-3), 40.3 (CH2Cl), 40.6 (CH2Cl), 50.2 (C-5), 52.7 (OMe), 65.2 (C-9), 70.5 (C-4), 70.7 (C-7), 71.2 (C-6), 74.7 (C-8), 88.7 (C-2), 108.6 (CMe2), 115.3 (q, JC,F = 288, CF3), 128.5, 129.0, 130.2, 136.1 (Ph), 157.8 (q, JC,F = 38, COCF3

• –7.42 (m, 1H, p-Ph), 7.61–7.63 (m, 2H, o-Ph), 8.74 (d, JNH,5 = 8.1 Hz, 1H, NH); 13C NMR (151 MHz, acetone-d6, δ, ppm, J, Hz) 38.2 (C-3), 41.5 (CH2Cl), 41.8 (CH2Cl), 50.9 (C-5), 52.7 (OMe), 69.0 (C-9), 69.4 (C-8), 70.2 (C-7), 71.8 (C-4), 72.3 (C-6), 90.3 (C-2), 117.0 (q, JC,F = 288, CF3), 129.8, 130.6

Synthesis of the 3’-O-sulfated TF antigen with a TEG-N₃ linker for glycodendrimersomes preparation to study lectin binding

• Mark Reihill,
• Hanyue Ma,
• Dennis Bengtsson and
• Stefan Oscarson

Beilstein J. Org. Chem. 2024, 20, 173–180, doi:10.3762/bjoc.20.17

• , Reveleris® silica cartiges 40 μm, Büchi Labortechnik AG®) and Biotage® SP4 HPFC (UV 200–500 nm, Biotage® SNAP KP-Sil 50 μm irregular silica, Biotage® AB). Instrumentation 1H NMR and 13C NMR spectra were recorded on Varian Inova spectrometers at 25 °C in chloroform-d (CDCl3), methanol-d4 (CD3OD), deuterium

• oxide (D2O) or DMSO-d6 ((CD3)2SO). 1H NMR spectra were standardised against the residual solvent peak (CDCl3, δ = 7.26 ppm; CD3OD, δ = 3.31 ppm; D2O, δ = 4.79 ppm; (CD3)2SO δ = 2.50 ppm); or internal trimethylsilane, δ = 0.00 ppm). 13C NMR spectra were standardised against the residual solvent peak

• (CDCl3, δ = 77.16 ppm; CD3OD, δ = 49.00 ppm; (CD3)2SO δ = 39.52 ppm and 13C NMR spectra recorded in D2O are unreferenced. All 13C NMR spectra are 1H decoupled. All NMR data are represented as follows: chemical shift (δ ppm), multiplicity (s = singlet, br s = broad singlet, d = doublet, app d = apparent

Photoinduced in situ generation of DNA-targeting ligands: DNA-binding and DNA-photodamaging properties of benzo[c]quinolizinium ions

• Julika Schlosser,
• Olga Fedorova,
• Yuri Fedorov and
• Heiko Ihmels

Beilstein J. Org. Chem. 2024, 20, 101–117, doi:10.3762/bjoc.20.11

• 4.07 (s, 3H, OCH3), 4.09 (s, 3H, CO2CH3), 4.23 (s, 3H, OCH3), 7.71 (s, 1H, 7-H), 8.11 (s, 1H, 10-H), 8.15 (d, 3J = 9 Hz, 1H, 5-H), 8.49 (d, 3J = 9 Hz, 1H, 4-H), 8.61 (d, 3J = 9 Hz, 1H, 6-H), 8.67 (dd, 3J = 9 Hz, 4J = 1 Hz, 1H, 3-H), 10.15 (s, 1H, 1-H); 13C NMR (150 MHz, CD3CN) δ 54.3 (CO2CH3), 57.4

• , 3J = 9 Hz, 4J = 1 Hz, 1H, 3-H), 8.40 (d, 3J = 9 Hz, 1H, 4-H), 8.53 (d, 3J = 9 Hz, 1H, 6-H), 9.88 (d, 4J = 1 Hz, 1H, 1-H); 13C NMR (125 MHz, CD3CN) δ 57.4 (OCH3), 58.3 (OCH3), 100.0 (C10), 109.9 (C7), 121.5 (C5), 124.5 (C6a), 130.2 (C4), 131.0 (C10a), 131.8 (C1), 132.7 (C2), 137.8 (C6), 138.4 (C3

• ), 4.20 (s, 1H, OCH3), 7.63 (s, 1H, 7-H), 8.01 (d, 3J = 9 Hz, 1H, 5-H), 8.05 (s, 1H, 10-H), 8.26 (dd, 3J = 9 Hz, 4J = 2 Hz, 1H, 3-H), 8.33 (d, 3J = 9 Hz, 1H, 4-H), 8.40 (d, 3J = 9 Hz, 1H, 6-H), 9.56 (s, 1H, 1-H); 13C NMR (125 MHz, CD3CN) δ 15.6 (CH3), 27.0 (CH2), 57.3 (OCH3), 58.1 (OCH3), 99.9 (C10

Multi-redox indenofluorene chromophores incorporating dithiafulvene donor and ene/enediyne acceptor units

• Christina Schøttler,
• Kasper Lund-Rasmussen,
• Line Broløs,
• Philip Vinterberg,
• Ema Bazikova,
• Viktor B. R. Pedersen and
• Mogens Brøndsted Nielsen

Beilstein J. Org. Chem. 2024, 20, 59–73, doi:10.3762/bjoc.20.8

• Systems X10/X50: 40–63 μm). TLC was performed using aluminum sheets covered with silica gel coated with fluorescent indicator. NMR spectra were recorded on a Bruker instrument at 500 MHz and 126 MHz for 1H and 13C NMR, respectively. Deuterated chloroform (CDCl3, 1H = 7.26 ppm, 13C = 77.16 ppm), deuterated

• –7.71 (m, 2H), 7.68 (d, J = 8.0 Hz, 1H), 7.58–7.44 (m, 2H), 7.44–7.35 (m, 3H), 4.50 (s, 4H), 2.44 (s, 3H), 1.43 (s, 9H), 1.36 (s, 9H) ppm; 13C NMR (126 MHz, CDCl3) δ 194.1, 152.7, 151.1, 148.7, 148.0, 144.7, 143.5, 142.3, 142.3, 138.8, 137.1, 135.5, 135.1, 133.6, 132.3, 131.4, 130.4, 129.1, 128.8, 127.7

• = 8.4 Hz, 4H), 7.64 (d, J = 8.0 Hz, 2H), 7.50 (d, J = 8.0 Hz, 2H), 7.34 (m, 6H), 7.29 (d, J = 8.4 Hz, 2H), 7.23 (s, 2H), 7.20 (s, 2H), 2.42 (s, 6H), 1.44 (s, 18H), 1.27 (s, 18H) ppm (E:Z ratio 4:1; 1H NMR signals reported for the E isomer); 13C NMR (126 MHz, CDCl3) δ 150.2, 149.9, 145.8, 143.6, 140.7

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

• similar phosphonium salt 2,4-di-tert-butyl-6-(triphenylphosphonium)phenolate features this particular signal at 6.27 ppm (4JHH = 2.7 Hz, 3JPH = 14.4 Hz [30]). In the 13C NMR spectra, the chemical shifts of the carbon atoms in positions 1 and 6 of the phenolate unit are particularly noteworthy. In the

• = 3.9 Hz) [30]. Compared to the parent phosphine 1 (155.9 ppm, 2JPC = 19.3 Hz) [35] a pronounced down-field shift occurred upon adduct formation, which suggests a considerable contribution of a quinonic resonance structure as benzoquinones exhibit 13C NMR shifts of about 188 ppm and hydroquinones of

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

• students, examples with combined 1D, 2D, and even some heteronuclear spectra can be used [42]. Here, one set including eight examples consisting exclusively of one-dimensional 1H and 13C NMR spectra and eight additional exercises including a combination of 1H, 13C, COSY, HSQC, and HMBC experiments provide

Cycloaddition reactions of heterocyclic azides with 2-cyanoacetamidines as a new route to C,N-diheteroarylcarbamidines

• Pavel S. Silaichev,
• Tetyana V. Beryozkina,
• Vsevolod V. Melekhin,
• Valeriy O. Filimonov,
• Andrey N. Maslivets,
• Vladimir G. Ilkin,
• Wim Dehaen and
• Vasiliy A. Bakulev

Beilstein J. Org. Chem. 2024, 20, 17–24, doi:10.3762/bjoc.20.3

• effect on the yield of the final compounds 3 observed. The structures of compounds 3a–u were confirmed by IR, 1H and 13C NMR spectroscopy (Figures S1‒S44 in Supporting Information File 1) as well as by high-resolution mass spectrometry (HRMS). X-ray data obtained for compound 3g gave us final proof of

• , 0.5 mmol; 1,4-dioxane (2 mL)) as a colorless powder; mp 225–226 °C; 1H NMR (400 MHz, DMSO-d6) δ 3.16 (s, 3H), 3.21 (s, 3H), 5.08 (s, 1H), 5.46 (s, 2H), 6.52 (s, 1H), 6.53 (s, 1H), 7.19 (br. s, 2H), 7.25–7.39 (m, 5H); 13C NMR (101 MHz, DMSO-d6) δ 27.1, 29.8, 48.4, 87.4, 120.9, 127.4, 127.6, 128.5

• NMR (400 MHz, DMSO-d6) δ 5.48 (s, 2H), 6.68 (s, 1H), 6.69 (s, 1H), 7.10 (d, J = 3.9 Hz, 1H), 7.24 (d, J = 6.9 Hz, 2H), 7.28–7.38 (m, 3H), 7.43 (d, J = 3.9 Hz, 1H), 8.42 (br. s, 1H), 9.15 (br. s, 1H); 13C NMR (101 MHz, DMSO-d6) δ 48.5, 112.6, 121.2, 127.2, 127.6, 128.5, 135.7, 138.8, 143.6, 153.5

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

• -chelate. In fact, the following convincing peaks were found in the NMR spectra: a singlet at 6.11 ppm, along with a quartet at 4.68 ppm (1H NMR spectrum), a peak at 83.3 ppm (13C NMR spectrum) and a singlet at −139.1 ppm (19F NMR spectrum) [109]. A simple washing with distilled water gave the

• In order to have an idea of the current efficiency in the electrogeneration of BF3 in BMIm-BF4 (a monoelectronic process, Scheme 1), we tried to quantitatively capture the electrogenerated BF3 with a tertiary base just at the end of the electrolysis. By a comparison between the 13C NMR peaks of the

• anolyte and the mixture was kept under stirring at room temperature for 30 min. Then, the neat anolyte was analysed by NMR (19F and 13C). The 19F NMR spectrum showed a new peak at −148.7 ppm and, to our great astonishment, we found only one set of signals in the 13C NMR spectrum (55.0, 42.8, 17.4, 16.0

Aldiminium and 1,2,3-triazolium dithiocarboxylate zwitterions derived from cyclic (alkyl)(amino) and mesoionic carbenes

• Nedra Touj,
• François Mazars,
• Guillermo Zaragoza and
• Lionel Delaude

Beilstein J. Org. Chem. 2023, 19, 1947–1956, doi:10.3762/bjoc.19.145

• cyclic (alkyl)(amino) or mesoionic carbenes (CAACs or MICs) onto carbon disulfide. Nine novel compounds were isolated and fully characterized by 1H and 13C NMR, FTIR, and HRMS techniques. Moreover, the molecular structures of two CAAC·CS2 and two MIC·CS2 betaines were determined by X-ray diffraction

• on 13C NMR spectroscopy (see below). We suspect that deleterious hydrophilic effects caused the subsequent decomposition of the CAAC·CS2 and MIC·CS2 zwitterions when an aqueous work-up was applied. Structural analysis Several analytical techniques were employed to characterize the nine aldiminium and

• significantly altered by the nature of the adjacent heterocycle, in line with a lack of electronic communication between these two moieties, as further discussed below. Contrastingly, the 13C NMR resonance for the carbenoid center of all the reagents and products used in this study was clearly affected by the

Construction of diazepine-containing spiroindolines via annulation reaction of α-halogenated N-acylhydrazones and isatin-derived MBH carbonates

• Xing Liu,
• Wenjing Shi,
• Jing Sun and
• Chao-Guo Yan

Beilstein J. Org. Chem. 2023, 19, 1923–1932, doi:10.3762/bjoc.19.143

• spiro[indoline-3,5'-[1,2]diazepine]-6'-carboxylates 5a–g in 63–77% yields (Scheme 3). The substituents on both substrates also showed little effect on the yields. The chemical structures were fully characterized by HRMS, IR, 1H and 13C NMR spectra. For demonstrating the synthetic value of this protocol

• (d, J = 8.0 Hz, 1H, ArH), 4.95–4.90 (m, 2H, CH2), 3.47 (d, J = 14.0 Hz, 1H, CH), 3.24 (d, J = 14.0 Hz, 1H, CH), 2.16 (s, 3H, CH3) ppm; 13C NMR (100 MHz, CDCl3) δ 173.8, 170.9, 159.6, 139.6, 138.4, 136.2, 135.2, 133.3, 133.2, 131.8, 130.7, 130.3, 130.0, 129.2, 128.9, 128.4, 127.9, 127.8, 127.4, 127.3

• –6.85 (m, 1H, ArH), 6.70 (d, J = 8.4 Hz, 1H, ArH), 5.02 (s, 2H, CH2), 3.65 (s, 3H, OCH3), 3.49 (d, J = 13.6 Hz, 1H, CH), 3.10 (d, J = 13.6 Hz, 1H, CH) ppm; 13C NMR (100 MHz, CDCl3) δ 176.3, 171.3, 165.8, 160.6, 141.1, 137.3, 135.9, 135.5, 133.8, 131.6, 130.6, 129.7, 128.9, 128.5, 128.4, 127.9, 127.8

Aromatic systems with two and three pyridine-2,6-dicarbazolyl-3,5-dicarbonitrile fragments as electron-transporting organic semiconductors exhibiting long-lived emissions

• Karolis Leitonas,
• Brigita Vigante,
• Dmytro Volyniuk,
• Audrius Bucinskas,
• Pavels Dimitrijevs,
• Sindija Lapcinska,
• Pavel Arsenyan and
• Juozas Vidas Grazulevicius

Beilstein J. Org. Chem. 2023, 19, 1867–1880, doi:10.3762/bjoc.19.139

• purification. Thin-layer chromatography (TLC) was performed using Merck Silica gel 60 F254 plates and visualized by UV (254 nm) fluorescence. Zeochem silica gel (ZEOprep 60/35–70 microns – SI23501) was used for column chromatography. 1H and 13C NMR spectra were recorded on a Bruker 400 spectrometer at 400 and

• (0.90 g, 89%) was obtained as bright yellow powder. Mp > 200 °C; 1H NMR (400 MHz, CDCl3) 8.11 (d, J = 1.9 Hz, 4H), 7.87–7.76 (m, 4H), 7.72 (d, J = 8.9 Hz, 4H), 7.49 (dd, J = 8.8, 1.9 Hz, 4H), 1.47 (s, 36H), 0.31 (d, J = 1.0 Hz, 9H); 13C NMR (101 MHz, CDCl3) 163.16, 154.51, 146.43, 136.98, 132.85, 132.58

• ) 8.11 (dd, J = 2.0, 0.6 Hz, 8H), 7.90 (s, 8H), 7.73 (dd, J = 8.8, 0.5 Hz, 8H), 7.49 (dd, J = 8.8, 2.0 Hz, 8H), 1.46 (s, 72H); 13C NMR (101 MHz, CDCl3) 162.83, 154.53, 154.50, 146.56, 146.52, 136.96, 133.59, 133.50, 133.11, 129.93, 129.72, 126.17, 125.78, 125.76, 125.54, 124.23, 124.21, 116.61, 114.01

Thienothiophene-based organic light-emitting diode: synthesis, photophysical properties and application

• Recep Isci and
• Turan Ozturk

Beilstein J. Org. Chem. 2023, 19, 1849–1857, doi:10.3762/bjoc.19.137

• properties indicated that the composition of thienothiophene, triphenylamine, and boron is a highly suitable combination for fluorescent organic electronics in display technology. Experimental General methods 1H and 13C NMR spectra were recorded on a Varian model NMR spectrometer (500 and 126 MHz) and

• = 8.7 Hz, 5H), 7.20 (d, J = 8.7 Hz, 2H), 7.13 (d, J = 7.6 Hz, 4H), 7.05 (t, J = 7.3 Hz, 2H), 6.95 (d, J = 8.7 Hz, 2H), 6.92 (d, J = 8.8 Hz, 2H), 3.86 (s, 3H); 13C NMR (126 MHz, CDCl3) δ 158.89, 147.36, 147.17, 142.04, 139.51, 135.73, 130.12, 129.87, 129.29, 128.34, 127.96, 125.86, 124.80, 123.24, 122.53

• ), 2.17 (s, 12H); 13C NMR (126 MHz, CDCl3) δ 158.92, 153.46, 151.26, 147.60, 147.20, 143.95, 141.05, 140.90, 138.50, 137.96, 132.59, 130.25, 129.86, 129.49, 129.33, 128.14, 127.85, 127.57, 125.01, 123.45, 122.08, 114.12, 55.23, 23.54, 21.22. Absorption and emission of DMB-TT-TPA (8) in THF. Figure 1 was

Substituent-controlled construction of A₄B₂-hexaphyrins and A₃B-porphyrins: a mechanistic evaluation

• Seda Cinar,
• Dilek Isik Tasgin and
• Canan Unaleroglu

Beilstein J. Org. Chem. 2023, 19, 1832–1840, doi:10.3762/bjoc.19.135

• -tosylimines. Experimental General method: All reagents and solvents were purchased from Sigma-Aldrich, Fisher Scientific, or Acros Organics and were used without further purification. 1H NMR (400 MHz), 13C NMR (100 MHz), and 19F NMR (376 MHz) spectra were recorded on a Bruker 400, Ultra Shield high

• -performance digital FT-NMR spectrometer. Data for 1H NMR, 13C NMR, and 19F NMR are reported as follows: chemical shift (δ, ppm), multiplicity (s = singlet, d = doublet, t = triplet, m = multiplet, q= quartet, bs = broad singlet, dd = doublet of doublets, td = triplet of doublets, qd = quartet of doublets