Spin and charge interactions between nanographene host and ferrocene

• Akira Suzuki,
• Yuya Miyake,
• Ryoga Shibata and
• Kazuyuki Takai

Beilstein J. Org. Chem. 2024, 20, 1011–1019, doi:10.3762/bjoc.20.89

• Fe2p peaks and the increase in shake-up peak intensity of the C1s in the XPS spectrum proved the emergence of charge-transfer host–guest interaction in FeCp2-ACFs-150, supported by the red-shift of the G-band in the Raman spectrum. The six-times enhancement in the spin concentration in FeCp2-ACFs-150

• photoelectron spectroscopy (XPS), Raman spectroscopy, Fourier-transform infrared (FTIR) spectroscopy, magnetic susceptibility, and electron-spin resonance (ESR). Experimental Commercially available ACFs (Kuraray, FR-20), of which the precursor was a phenol-resin, were pre-heat-treated in a glass tube at 200 °C

• surface of ACFs, which were removed by heating the FeCp2-treated ACFs at 150 °C for 3 hours without FeCp2 vapor. XPS spectra were recorded using a PHI-5600 (ULVAC-PHI) with an Al Kα X-ray source (1486.7 eV) for samples mounted on an indium film. Raman spectroscopy measurements were performed by LabRAM HR

Preparing a liquid crystalline dispersion of carbon nanotubes with high aspect ratio

• Keiko Kojima,
• Nodoka Kosugi,
• Hirokuni Jintoku,
• Kazufumi Kobashi and
• Toshiya Okazaki

Beilstein J. Org. Chem. 2024, 20, 52–58, doi:10.3762/bjoc.20.7

• carbon nanotube dispersions with high aspect ratios, we utilized DWCNTs obtained from Shenzhen Nanotech Port Co. Ltd. Supporting Information File 1 provides characterization details. Briefly, the Raman G/D ratio was approximately 37 (Supporting Information File 1, Figure S1d), indicating high

• flowing air (200 mL/min) at a ramping rate of 1 °C/min. The Raman and absorption spectra were obtained from DWCNT thin film on a silicon substrate. The DWCNT thin film was prepared using vacuum filtration. Raman measurements were conducted using a HORIBA T64000 532 nm laser, while far-infrared (FIR

Charge carrier transport in perylene-based and pyrene-based columnar liquid crystals

• Alessandro L. Alves,
• Simone V. Bernardino,
• Carlos H. Stadtlober,
• Edivandro Girotto,
• Giliandro Farias,
• Rodney M. do Nascimento,
• Sergio F. Curcio,
• Thiago Cazati,
• Marta E. R. Dotto,
• Juliana Eccher,
• Leonardo N. Furini,
• Hugo Gallardo,
• Harald Bock and
• Ivan H. Bechtold

Beilstein J. Org. Chem. 2023, 19, 1755–1765, doi:10.3762/bjoc.19.128

• given in Table 1. Raman spectra of both compounds were acquired off-resonance (Figure 1). Compound 1 presents the main peak at 1609 cm−1 assigned to C=C stretching from the chromophore, a peak of intermediate intensity at 1292 cm−1 assigned to C–H bending and ring stretching, and a less intense peak at

• materials. Experimental Raman spectra were obtained in an Anton Paar spectrometer, Cora 5001 model, under an excitation laser line at 785 nm and 450 mW power source. The exposure time was around 160 ms and 1 accumulation. The sample powder was placed in a glass slide under the objective lens and performed

• surface. Images of the complex geometries were obtained using the Chemcraft program (http://www.chemcraftprog.com). Raman spectra of 1 (a) and 2 (b) in powder. XRD measurements of 1 (a) and 2 (b) captured on cooling from the isotropic phase, indicating the Miller indices. Absorption and PL in chloroform

Exploring the role of halogen bonding in iodonium ylides: insights into unexpected reactivity and reaction control

• Carlee A. Montgomery and
• Graham K. Murphy

Beilstein J. Org. Chem. 2023, 19, 1171–1190, doi:10.3762/bjoc.19.86

• have been evaluated extensively through both qualitative and quantitative means. Methods of evaluation have included X-ray crystallography and spectroscopy (e.g., microwave, IR, Raman, NMR, NQR), as well as through computational determination of their electrostatic VS,max potentials (Figure 2), their

Thermally activated delayed fluorescence (TADF) emitters: sensing and boosting spin-flipping by aggregation

• Ashish Kumar Mazumdar,
• Gyana Prakash Nanda,
• Nisha Yadav,
• Upasana Deori,
• Upasha Acharyya,
• Bahadur Sk and
• Pachaiyappan Rajamalli

Beilstein J. Org. Chem. 2022, 18, 1177–1187, doi:10.3762/bjoc.18.122

• Ashish Kumar Mazumdar Gyana Prakash Nanda Nisha Yadav Upasana Deori Upasha Acharyya Bahadur Sk Pachaiyappan Rajamalli Materials Research Centre, Indian Institute of Science, C. V. Raman Road, Bangalore, Karnataka, 560012, India 10.3762/bjoc.18.122 Abstract Metal-free organic emitters with

• , for C. V. Raman Fellowship. U. D. and N. Y. thank IISc for doctoral fellowship. P. R. thanks IISc for generous financial support and the Science & Engineering Research Board (SERB), India, for the SERB-Power Grant (SPG, Grant No: SPG/2020/000107). P. R. also acknowledges Rekha Rao Young Investigator

Mechanochemical halogenation of unsymmetrically substituted azobenzenes

• Dajana Barišić,
• Mario Pajić,
• Ivan Halasz,
• Darko Babić and
• Manda Ćurić

Beilstein J. Org. Chem. 2022, 18, 680–687, doi:10.3762/bjoc.18.69

• reaction dynamics and characterization of the products was achieved by in situ Raman and ex situ NMR spectroscopy and PXRD analysis. A strong influence of the different 4,4’-substituents of azobenzene on the halogenation time and mechanism was found. Keywords: azo compounds; halogenation; mechanochemistry

• -bromosuccinimide (NBS) under neat grinding (NG) and liquid-assisted grinding (LAG) conditions in a ball mill [51]. Insight into the dynamics of the formation of reaction intermediates and products was obtained by in situ Raman monitoring that provided information on the nature of the catalytically active PdII

• azobenzene with NXS and Pd(OAc)2 as precatalyst in the presence of TsOH and MeCN as solid and liquid additives, respectively, led to the ortho-halogenated products relative to the azo group of the azobenzenes. In situ Raman monitoring of these reactions confirmed that the most favorable reaction pathway is

Recent developments and trends in the iron- and cobalt-catalyzed Sonogashira reactions

• Surendran Amrutha,
• Sankaran Radhika and
• Gopinathan Anilkumar

Beilstein J. Org. Chem. 2022, 18, 262–285, doi:10.3762/bjoc.18.31

• phenylacetylene in the presence of a series of PdCo bimetallic nanoparticles with different compositions on graphite sheets as highly active catalysts (Scheme 27) [40]. The catalyst was prepared by a chemical reduction method and characterized by various techniques like Raman, XRD, TEM, and XPS. The Pd/Co(1:1)NPs

Multi-faceted reactivity of N-fluorobenzenesulfonimide (NFSI) under mechanochemical conditions: fluorination, fluorodemethylation, sulfonylation, and amidation reactions

• José G. Hernández,
• Karen J. Ardila-Fierro,
• Dajana Barišić and
• Hervé Geneste

Beilstein J. Org. Chem. 2022, 18, 182–189, doi:10.3762/bjoc.18.20

• solution, the mechanochemical reactions were accomplished in the absence of solvents, in short reaction times, and in yields comparable to or higher than their solvent-based counterparts. Keywords: amidation; ball mill; fluorination; in situ monitoring; mechanochemistry; NFSI; Raman monitoring

• performed in situ reaction monitoring of the milling process by Raman spectroscopy [32][33]. In an experiment milling 1c with NFSI (1 equiv) we observed the consumption of NFSI after ca. 30 min of milling as evidenced by a reduction in the intensity of the band at 1197 cm−1 of NFSI (Figure S3 in Supporting

• Information File 1). However, the very strong bands around 998 cm−1 (in-plane bending; phenyl ring), 1177 cm−1 (stretching; SO2), and 1583 cm−1 (stretching; phenyl ring) of NFSI and byproducts [(PhSO2)2NH [34], and (PhSO2)2NCH3], prevented the observation of the less Raman active fluorinated products 2c and

Constrained thermoresponsive polymers – new insights into fundamentals and applications

• Patricia Flemming,
• Alexander S. Münch,
• Andreas Fery and
• Petra Uhlmann

Beilstein J. Org. Chem. 2021, 17, 2123–2163, doi:10.3762/bjoc.17.138

An initiator- and catalyst-free hydrogel coating process for 3D printed medical-grade poly(ε-caprolactone)

• Jochen Löblein,
• Thomas Lorson,
• Miriam Komma,
• Tobias Kielholz,
• Maike Windbergs,
• Paul D. Dalton and
• Robert Luxenhofer

Beilstein J. Org. Chem. 2021, 17, 2095–2101, doi:10.3762/bjoc.17.136

• photopolymerization for the hydrophilic modification of microfiber scaffolds obtained from hydrophobic medical-grade poly(ε-caprolactone) via melt-electrowriting. Contact angle measurements and Raman spectroscopy confirms the formation of a more hydrophilic coating of poly(2-hydroxyethyl methacrylate). Apart from

• ), however, this morphology is highly irregular. A change in wetting behavior could be demonstrated, and toluidine blue staining indicates successful SIPGP of HEMA on PCL scaffolds. However, to prove that this material is indeed PHEMA, we performed confocal Raman microscopy on the samples, which allows a

• symmetrical stretching vibration [ν(C–O–C)] of ester groups (Figure 2C, blue and red circles). With Raman imaging and the corresponding spectra, the presence of PHEMA on the PCL MEW scaffolds was clearly verified (Figure 2C and Figure 2D), especially regarding the material spanning the boxes. Unfortunately

A comprehensive review of flow chemistry techniques tailored to the flavours and fragrances industries

• Guido Gambacorta,
• James S. Sharley and
• Ian R. Baxendale

Beilstein J. Org. Chem. 2021, 17, 1181–1312, doi:10.3762/bjoc.17.90

• , have also been developed. Other in-line techniques employing simple UV [67][68][69][70], MS [71][72][73], and Raman [74][75][76][77] analysis have also been successfully applied enabling efficient optimisation and generation of new reaction chemistry. Flow-based chemical processing has elevated other

Mesoionic tetrazolium-5-aminides: Synthesis, molecular and crystal structures, UV–vis spectra, and DFT calculations

• Vladislav A. Budevich,
• Sergei V. Voitekhovich,
• Alexander V. Zuraev,
• Vadim E. Matulis,
• Vitaly E. Matulis,
• Alexander S. Lyakhov,
• Ludmila S. Ivashkevich and
• Oleg A. Ivashkevich

Beilstein J. Org. Chem. 2021, 17, 385–395, doi:10.3762/bjoc.17.34

• recorded on a Bruker Vertex 70 spectrometer in diamond cell accessory. For Raman spectra registration, an Ocean Optics ID RAMAN READER (785 nm) spectrometer was used. Experimental procedures The experimental procedures are given in Supporting Information File 1. Computation details Calculations of the UV

Control over size, shape, and photonics of self-assembled organic nanocrystals

• Chen Shahar,
• Yaron Tidhar,
• Yunmin Jung,
• Haim Weissman,
• Sidney R. Cohen,
• Ronit Bitton,
• Iddo Pinkas,
• Gilad Haran and
• Boris Rybtchinski

Beilstein J. Org. Chem. 2021, 17, 42–51, doi:10.3762/bjoc.17.5

• obtain a stable and smooth white-light continuum. The resulting beam is passed through a Raman notch filter in order to remove the remains of the 800 nm fundamental beam from the probe white-light continuum. The pump and probe pulses are crossed in the sample at a small angle while maintaining a magic

UV resonance Raman spectroscopy of the supramolecular ligand guanidiniocarbonyl indole (GCI) with 244 nm laser excitation

• Tim Holtum,
• Vikas Kumar,
• Daniel Sebena,
• Jens Voskuhl and
• Sebastian Schlücker

Beilstein J. Org. Chem. 2020, 16, 2911–2919, doi:10.3762/bjoc.16.240

• , Universitätsstrasse 7, 45141 Essen, Germany 10.3762/bjoc.16.240 Abstract Ultraviolet resonance Raman (UVRR) spectroscopy is a powerful vibrational spectroscopic technique for the label-free monitoring of molecular recognition of peptides or proteins with supramolecular ligands such as guanidiniocarbonyl pyrroles

• (GCPs). The use of UV laser excitation enables Raman binding studies of this class of supramolecular ligands at submillimolar concentrations in aqueous solution and provides a selective signal enhancement of the carboxylate binding site (CBS). A current limitation for the extension of this promising

• the results from density functional theory (DFT) calculations. Keywords: GCI; GCP; guanidiniocarbonyl indole; guanidiniocarbonyl pyrrole; UVRR; Raman spectroscopy; resonance Raman; Introduction Supramolecular ligands are capable to selectively bind to peptides and proteins via reversible non

Optical detection of di- and triphosphate anions with mixed monolayer-protected gold nanoparticles containing zinc(II)–dipicolylamine complexes

• Lena Reinke,
• Julia Bartl,
• Marcus Koch and
• Stefan Kubik

Beilstein J. Org. Chem. 2020, 16, 2687–2700, doi:10.3762/bjoc.16.219

• sensing [1][2][3][4][5][6]. The analyte can be detected by relying on the enhancement of the Raman scattering intensity, if it is bound close to the gold surface (surface enhanced Raman scattering, SERS), for example, or by the release from the metal surface of a chromophore the fluorescence of which is

Water-soluble host–guest complexes between fullerenes and a sugar-functionalized tribenzotriquinacene assembling to microspheres

• Si-Yuan Liu,
• Xin-Rui Wang,
• Man-Ping Li,
• Wen-Rong Xu and
• Dietmar Kuck

Beilstein J. Org. Chem. 2020, 16, 2551–2561, doi:10.3762/bjoc.16.207

• Ka = (2.20 ± 0.16) × 105 M−1, respectively. The binding affinity between TBTQ-(OG)6 and C60 was further verified by Raman spectroscopy. The geometry of the complex of TBTQ-(OG)6 with C60 deduced from DFT calculations indicates that the driving force of the complexation is mainly due to the

• equivalents of TBTQ-(OG)6, while the maximum solubility of C70 was about 0.17 mg/mL. Raman spectroscopy has proven to be a useful tool for the characterization of carbon nanomaterials [51][52]. The Raman spectra of TBTQ-(OG)6, C60 and TBTQ-(OG)6 C60 are displayed in Figure 5. The TBTQ-(OG)6 shows a weak peak

• at 1112 cm−1. The pristine C60-fullerene shows characteristic peaks at 494 cm−1 (Ag-breathing mode), 1467 cm−1 (Ag-pentagonal pinch mode), as well as signals at 272 cm−1 and 1572 cm−1 (Hg modes) [53]. The Raman spectrum of TBTQ-(OG)6 C60 clearly shows the presence of TBTQ-(OG)6 and fullerene, and

Synergy between supported ionic liquid-like phases and immobilized palladium N-heterocyclic carbene–phosphine complexes for the Negishi reaction under flow conditions

• Edgar Peris,
• Raúl Porcar,
• María Macia,
• Jesús Alcázar,
• Eduardo García-Verdugo and
• Santiago V. Luis

Beilstein J. Org. Chem. 2020, 16, 1924–1935, doi:10.3762/bjoc.16.159

• mmol Cl/g,) was used as the starting material for the immobilization of N-arylimidazoles 2a and 2b, following the traditional alkylation protocol [18][19]. The preparation of these modified polymers was monitored by FT–ATR–IR, FT-Raman using a micro-spectroscopy accessory and the NBP test [20][21]. The

Natural dolomitic limestone-catalyzed synthesis of benzimidazoles, dihydropyrimidinones, and highly substituted pyridines under ultrasound irradiation

• Kumar Godugu,
• Venkata Divya Sri Yadala,
• Mohammad Khaja Mohinuddin Pinjari,
• Trivikram Reddy Gundala,
• Lakshmi Reddy Sanapareddy and
• Chinna Gangi Reddy Nallagondu

Beilstein J. Org. Chem. 2020, 16, 1881–1900, doi:10.3762/bjoc.16.156

• pyridines via C–N, C–C, and C–S bond formations in a mixture of ethanol and H2O under ultrasound irradiation. The catalyst is characterized by XRD, FTIR, Raman spectroscopy, SEM, and EDAX analysis. The main advantages of this methodology include the wide substrate scope, cleaner reaction profile, short

• indicators. The catalyst was characterized by XRD, IR, Raman, SEM, and EDAX analysis. The chemical composition of the NDL was determined by adopting a standard quantitative analysis [75]. The obtained results are summarized in Table 1. The basic strength of the NDL catalyst (H_) was measured using Hammett

• were ascribed to the 111, 211, 400, 422, 511, and 440 plane, respectively, of iron oxides (JCPDS card file 39-1346 and JCPDS card file 19-629) [79][80]. The above results were supported by FTIR and Raman characterization studies of the catalyst (vide infra). The FTIR spectrum of the catalyst is shown

Mono- and bithiophene-substituted diarylethene photoswitches with emissive open or closed forms

• A. Lennart Schleper,
• Mariano L. Bossi,
• Vladimir N. Belov and
• Stefan W. Hell

Beilstein J. Org. Chem. 2019, 15, 2344–2354, doi:10.3762/bjoc.15.227

• at ca. 390 nm (a and b) are Raman bands of the solvent. Fatigue resistances of compounds SyOTh1 (A and B) and SyTh1 (C). Parts A and C show the absorbance at certain wavelengths after cyclization (top values) and cycloreversion (bottom values). Part B shows the change in absorbance at 478 nm for each

Mechanochemical Friedel–Crafts acylations

• Mateja Đud,
• Anamarija Briš,
• Iva Jušinski,
• Davor Gracin and
• Davor Margetić

Beilstein J. Org. Chem. 2019, 15, 1313–1320, doi:10.3762/bjoc.15.130

• studied by in situ Raman and ex situ IR spectroscopy. Keywords: ball milling; Friedel–Crafts reaction; mechanochemistry; Introduction The Friedel–Crafts reaction (FCR) is a very powerful tool in organic chemistry for the synthesis of aromatic ketones. It is of great industrial importance and widely used

• demonstrate that quinones could be prepared by simple one-pot FC protocols in the case of reactive aromatics. In situ Raman spectroscopy [60] was applied to study mechanistic aspects of the solid state reaction of phthalic anhydride with p-xylene. Raman spectra were simulated and positions of signals for

• transient reactive intermediates were predicted by density functional theory method B3LYP/6-31G* (Supporting Information File 1) [61]. The stretching of the +C≡O bond of the acylium ion was predicted to be at about 2300 cm−1. Raman spectroscopy revealed that the complexation of phthalic anhydride with AlCl3

Unexpected polymorphism during a catalyzed mechanochemical Knoevenagel condensation

• Sebastian Haferkamp,
• Andrea Paul,
• Adam A. L. Michalchuk and
• Franziska Emmerling

Beilstein J. Org. Chem. 2019, 15, 1141–1148, doi:10.3762/bjoc.15.110

• triclinic product. Inclusion of catalyst in the final product, as evidenced by mass spectrometric analysis, suggests this complex polymorphic pathway may be due to seeding effects. Multivariate analysis for the in situ Raman spectra supports this complex formation pathway, and offers a new approach to

• reaction environment. It was subsequently demonstrated how a combination of different in situ methods can provide more thorough investigation of mechanochemical reaction mechanisms [14][15][16]. Of particular benefit to synthetic reactions, such as C–C bond formation [17][18], the use of Raman spectroscopy

• is of great interest. The characteristic bands are usually well separated, and the course of the reaction can be followed easily. The advantage of Raman spectroscopy was recently demonstrated [19], where its combination with XRPD allowed monitoring of the mechanochemically catalyzed Knoevenagel

DABCO- and DBU-promoted one-pot reaction of N-sulfonyl ketimines with Morita–Baylis–Hillman carbonates: a sequential approach to (2-hydroxyaryl)nicotinate derivatives

• Soumitra Guin,
• Raman Gupta,
• Debashis Majee and
• Sampak Samanta

Beilstein J. Org. Chem. 2018, 14, 2771–2778, doi:10.3762/bjoc.14.254

• Soumitra Guin Raman Gupta Debashis Majee Sampak Samanta Discipline of Chemistry, Indian Institute of Technology Indore, Simrol, Indore, 453552, Madhya Pradesh, India 10.3762/bjoc.14.254 Abstract An intriguing DABCO-catalyzed and DBU-promoted one-pot synthesis of an important class of (2

Synergistic electrodeposition of bilayer films and analysis by Raman spectroscopy

• Saadeldin E. T. Elmasly,
• Luca Guerrini,
• Joseph Cameron,
• Alexander L. Kanibolotsky,
• Neil J. Findlay,
• Karen Faulds and
• Peter J. Skabara

Beilstein J. Org. Chem. 2018, 14, 2186–2189, doi:10.3762/bjoc.14.191

• successfully demonstrated. Moreover, careful control of the electrochemical conditions allows the degree of doping to be effectively altered for one of the polymer layers. Raman spectroscopy confirmed the formation and doped states of the PEDOT/PEDTT bilayer. The electrochemical deposition of a bilayer

• ) raises the possibility of depositing a subsequent layer via solution-processing. Keywords: bilayer; electropolymerisation; PEDOT; PEDTT; Raman; Findings Fabrication of multilayer organic electronic devices has been extensively researched in the past 20 years, resulting in numerous processes and

• PEDOT layer remains predominantly doped. In order to support the formation of a PEDOT/PEDTT bilayer using this technique and to clarify the nature of doping in the two layers, freshly fabricated bilayers (using 10−4 M monomer solution) were grown on ITO and analysed by Raman spectroscopy, alongside

Solvent-free copper-catalyzed click chemistry for the synthesis of N-heterocyclic hybrids based on quinoline and 1,2,3-triazole

• Martina Tireli,
• Silvija Maračić,
• Stipe Lukin,
• Marina Juribašić Kulcsár,
• Dijana Žilić,
• Mario Cetina,
• Ivan Halasz,
• Silvana Raić-Malić and
• Krunoslav Užarević

Beilstein J. Org. Chem. 2017, 13, 2352–2363, doi:10.3762/bjoc.13.232

• the reaction and generation of highly luminescent compounds which hindered in situ monitoring by Raman spectroscopy. However, in situ monitoring of the milling processes was enabled by using Cu(0) catalysts in the form of brass milling media which offered a direct insight into the reaction pathway of

• spin resonance (ESR) spectroscopy; in situ Raman monitoring; mechanochemistry; quinoline; solid-state click chemistry; Introduction The copper-catalyzed azide–alkyne cycloaddition (CuAAC) represents a prime example of click chemistry. Click chemistry describes “a set of near-perfect” reactions [1] for

• states for the mechanochemical CuAAC reaction of target quinoline derivatives and p-substituted phenyl azides. We have also investigated the effect of the p-substituent in the azide on the reaction progress and yields. Direct monitoring by in situ Raman spectroscopy was used to gain an insight into the

Structural diversity in the host–guest complexes of the antifolate pemetrexed with native cyclodextrins: gas phase, solution and solid state studies

• Magdalena Ceborska,
• Magdalena Zimnicka,
• Aneta Aniela Kowalska,
• Kajetan Dąbrowa and
• Barbara Repeć

Beilstein J. Org. Chem. 2017, 13, 2252–2263, doi:10.3762/bjoc.13.222

• equivalent – methyl α-D-glucopyranoside – was investigated for a deeper understanding of the type of host–guest interactions. Solid state studies of PTX/CDs were performed using FTIR–ATR and Raman spectroscopy techniques. Keywords: antifolate; cyclodextrin; hydrophobic interactions; inclusion complexes

• ; pemetrexed; supramolecular chemistry; Introduction Herein, supramolecular host–guest complexes of the potent folic acid inhibitor pemetrexed (PTX, Figure 1a) with native cyclodextrins (α-, β- and γ-CDs, Figure 1b) in the gas phase (MS), in solution (NMR, UV–vis) and in the solid state (Raman, FTIR–ATR) were

• methods – FTIR–ATR and Raman were used for describing the way of PTX-CD interactions. The IR spectroscopy in the region characteristic for δ-HOH bending of water molecules attached to CDs (1600–1700 cm−1) is usually employed for tracking of the inclusion complex formation, however, Raman spectra of this