α-Photooxygenation of chiral aldehydes with singlet oxygen

• Dominika J. Walaszek,
• Magdalena Jawiczuk,
• Jakub Durka,
• Olga Drapała and
• Dorota Gryko

Beilstein J. Org. Chem. 2019, 15, 2076–2084, doi:10.3762/bjoc.15.205

• chemical shifts (δ) and coupling constants (J) are expressed in ppm and Hertz, respectively. High-resolution mass spectrometry (HRMS) data were obtained at the Synapt G2-S HDMS mass spectrometer equipped with an electrospray ion source and q-TOF type mass analyzer. Specific rotation was measured on a JASCO

Attempted synthesis of a meta-metalated calix[4]arene

• Christopher D. Jurisch and
• Gareth E. Arnott

Beilstein J. Org. Chem. 2019, 15, 1996–2002, doi:10.3762/bjoc.15.195

• strategy involved using a mesoionic carbene to direct C–H activation, but proved to form an unexpectedly unstable intermediate that was identified through high-resolution mass spectrometry. On route to our target, a new optimized method to mononitrocalix[4]arenes was developed, including optimized and high

Morphology-tunable and pH-responsive supramolecular self-assemblies based on AB₂-type host–guest-conjugated amphiphilic molecules for controlled drug delivery

• Yang Bai,
• Cai-ping Liu,
• Di Chen,
• Long-hai Zhuo,
• Huai-tian Bu and
• Wei Tian

Beilstein J. Org. Chem. 2019, 15, 1925–1932, doi:10.3762/bjoc.15.188

• –3.9, 4.3–4.9 and 5.6–5.9 and protons of BM at δ = 7.0–8.4 could be observed obviously in the 1H NMR spectrum of β-CD-BM2 (Figure S1B-d, Supporting Information File 1). Furthermore, the molecular weight of β-CD-BM2 (Figure S1C, Supporting Information File 1) measured by high-resolution mass

• spectrometry was 1497.5266 [M + H+], which was in accordance with the theoretical value of 1496.5236. On the basis of the above results, AB2-type host–guest-conjugated amphiphilic monomer β-CD-BM2 has been successfully synthesized. Supramolecular self-assembly behavior of β-CD-BM2 The morphology of the self

Complexation of 2,6-helic[6]arene and its derivatives with 1,1′-dimethyl-4,4′-bipyridinium salts and protonated 4,4'-bipyridinium salts: an acid–base controllable complexation

• Jing Li,
• Qiang Shi,
• Ying Han and
• Chuan-Feng Chen

Beilstein J. Org. Chem. 2019, 15, 1795–1804, doi:10.3762/bjoc.15.173

• reaction of 4,4′-bipyridine with concentrated HCl in acetonitrile followed by counteranion exchange with sodium tetrakis[3,5-di(trifluoromethyl)phenyl]borate (NaBArF) in dichloromethane. The new compounds were confirmed by NMR spectroscopy and high-resolution mass spectrometry (Supporting Information File

Synthesis, enantioseparation and photophysical properties of planar-chiral pillar[5]arene derivatives bearing fluorophore fragments

• Guojuan Li,
• Chunying Fan,
• Guo Cheng,
• Wanhua Wu and
• Cheng Yang

Beilstein J. Org. Chem. 2019, 15, 1601–1611, doi:10.3762/bjoc.15.164

• -resolution mass spectrometry (HRMS, Supporting Information File 1, Figures S19–S21). Photophysical properties The photophysical properties were investigted by UV–vis absorption and fluorescence spectroscopy, as well as through fluorescence decay measurements. As shown in Figure 1a, the UV–vis spectrum of P5A

• from CuSO4 and sodium ascorbate through extraction with Et2O/water. Further purification of the crude product was carried out by silica gel column chromatography (dichloromethane/methanol 30:1) to afford P5A-DPA in 72% yield. The structure of P5A-DPA was characterized by 1H NMR, 13C NMR and high

Synthesis of ([1,2,4]triazolo[4,3-a]pyridin-3-ylmethyl)phosphonates and their benzo derivatives via 5-exo-dig cyclization

• Aleksandr S. Krylov,
• Artem A. Petrosian,
• Julia L. Piterskaya,
• Nataly I. Svintsitskaya and
• Albina V. Dogadina

Beilstein J. Org. Chem. 2019, 15, 1563–1568, doi:10.3762/bjoc.15.159

• spectroscopy, high-resolution mass spectrometry, as well as single crystal X-ray diffraction. Next, under the conditions applied for the preparation of compounds 3–8, the reaction of chloroethynylphosphonates with 2-hydrazinylquinoline (1g) and 1-hydrazinylisoquinoline (1h) resulted in the formation of [1,2,4

Fluorine-containing substituents: metabolism of the α,α-difluoroethyl thioether motif

• Andrea Rodil,
• Alexandra M. Z. Slawin,
• Nawaf Al-Maharik,
• Ren Tomita and
• David O’Hagan

Beilstein J. Org. Chem. 2019, 15, 1441–1447, doi:10.3762/bjoc.15.144

• 19F NMR spectrum consistent with non-equivalence of the fluorines, immediately indicative of sulfoxide formation. Isolation and subsequent 1H and 19F NMR analyses as well as high-resolution mass spectrometry secured the identity of these metabolites as sulfoxides 6 and 7 and sulfone 8. The structure

• accurate mass spectrometry. 19F{1H} and 13C{1H}) NMR spectra were recorded on Bruker Avance III 500 or Bruker Avance III 500 HD spectrometers (500 MHz 1H, 476 MHz 19F, 126 MHz 13C). High-resolution mass spectrometry was acquired using electrospray ionisation (ESI), on a ThermoFisher Excalibur Orbitrap

Selenophene-containing heterotriacenes by a C–Se coupling/cyclization reaction

• Pierre-Olivier Schwartz,
• Sebastian Förtsch,
• Astrid Vogt,
• Elena Mena-Osteritz and
• Peter Bäuerle

Beilstein J. Org. Chem. 2019, 15, 1379–1393, doi:10.3762/bjoc.15.138

• (Supporting Information File 1, Figures S1–S4), high-resolution mass spectrometry, and elemental analysis. In the 1H NMR spectra, the influence of the selenium atoms in triacenes DST 3 and DSS 4 results in substantial deshielding of the protons compared to bithiophene-based derivates 1 and 2, which is in

A chemically contiguous hapten approach for a heroin–fentanyl vaccine

• Yoshihiro Natori,
• Candy S. Hwang,
• Lucy Lin,
• Lauren C. Smith,
• Bin Zhou and
• Kim D. Janda

Beilstein J. Org. Chem. 2019, 15, 1020–1031, doi:10.3762/bjoc.15.100

• NMR, 13C NMR, and high-resolution mass-spectrometry signals. Supporting Information File 128: Supporting experimental results. Supporting Information File 129: Experimental procedures for compounds 1–53. Supporting Information File 130: NMR spectra of compounds 1–53. Acknowledgements This work was

Synthesis of 2H-furo[2,3-c]pyrazole ring systems through silver(I) ion-mediated ring-closure reaction

• Vaida Milišiūnaitė,
• Rūta Paulavičiūtė,
• Eglė Arbačiauskienė,
• Vytas Martynaitis,
• Wolfgang Holzer and
• Algirdas Šačkus

Beilstein J. Org. Chem. 2019, 15, 679–684, doi:10.3762/bjoc.15.62

• ]pyrazoles was explored (Scheme 2). For substrates 3b–j, the reactions were complete after 14 hours at 120 °C, and products 4b–j were generated in fair to excellent yields. The structural assignments of 4a–j were based on multinuclear NMR and IR spectroscopy as well as high-resolution mass spectrometry (HRMS

Polyaminoazide mixtures for the synthesis of pH-responsive calixarene nanosponges

• Antonella Di Vincenzo,
• Antonio Palumbo Piccionello,
• Alberto Spinella,
• Delia Chillura Martino,
• Marco Russo and
• Paolo Lo Meo

Beilstein J. Org. Chem. 2019, 15, 633–641, doi:10.3762/bjoc.15.59

• CaNS-I and CaNS-II, respectively. Owing to their complex nature, mixtures I and II were first characterized by means of HR-ESIMS techniques. High-resolution mass spectrometry, in fact, enables to unambiguously identify the molecular formula of each compound present in the mixtures, and to determine

Synthesis and fluorescent properties of N(9)-alkylated 2-amino-6-triazolylpurines and 7-deazapurines

• Andrejs Šišuļins,
• Jonas Bucevičius,
• Yu-Ting Tseng,
• Irina Novosjolova,
• Kaspars Traskovskis,
• Ērika Bizdēna,
• Huan-Tsung Chang,
• Sigitas Tumkevičius and
• Māris Turks

Beilstein J. Org. Chem. 2019, 15, 474–489, doi:10.3762/bjoc.15.41

• determined using QuantaMaster 40 steady state spectrofluorometer (Photon Technology International, Inc.) equipped with 6 inch integrating sphere by LabSphere, using a florescence standard of quinine sulfate in 0.1 M H2SO4 as a reference. High-resolution mass spectrometry (HRMS) analyses were carried out on a

LCST phase behavior of benzo-21-crown-7 with different alkyl chains

• Yan Deng,
• Xing Li,
• Qiao Zhang,
• Zheng Luo,
• Chengyou Han and
• Shengyi Dong

Beilstein J. Org. Chem. 2019, 15, 437–444, doi:10.3762/bjoc.15.38

• and molecular structures. Results and Discussion Two series of B21C7s, comprising carbamate-based linkers 3a–e and urea-based linkers 5a–e, were designed and synthesized, as shown in Scheme 1 and Scheme 2. All structures were confirmed by NMR spectroscopy and high-resolution mass spectrometry (details

Syntheses and chemical properties of β-nicotinamide riboside and its analogues and derivatives

• Mikhail V. Makarov and
• Marie E. Migaud

Beilstein J. Org. Chem. 2019, 15, 401–430, doi:10.3762/bjoc.15.36

One-pot synthesis of epoxides from benzyl alcohols and aldehydes

• Edwin Alfonzo,
• Jesse W. L. Mendoza and
• Aaron B. Beeler

Beilstein J. Org. Chem. 2018, 14, 2308–2312, doi:10.3762/bjoc.14.205

• characterization for all new compounds described herein. Acknowledgements Financial support from Boston University and National Science Foundation (ABB CHE-1555300) is gratefully acknowledged. We thank Dr. Norman Lee (Boston University) for high-resolution mass spectrometry data. NMR (CHE-0619339) and MS

Hypervalent iodine compounds for anti-Markovnikov-type iodo-oxyimidation of vinylarenes

• Igor B. Krylov,
• Stanislav A. Paveliev,
• Mikhail A. Syroeshkin,
• Alexander A. Korlyukov,
• Pavel V. Dorovatovskii,
• Yan V. Zubavichus,
• Gennady I. Nikishin and
• Alexander O. Terent’ev

Beilstein J. Org. Chem. 2018, 14, 2146–2155, doi:10.3762/bjoc.14.188

• higher (25% on average) than that of N-hydroxysuccinimide (2b). Structures of the iodo-oxyimides 3aa–ka, 3ab–db, 3fb, 3hb and 3kb were confirmed by 1D and 2D NMR spectroscopy, IR spectroscopy, high-resolution mass spectrometry and elemental analysis. An additional confirmation of the structure of 3ca was

A self-assembled photoresponsive gel consisting of chiral nanofibers

• Lei Zou,
• Dan Han,
• Zhiyi Yuan,
• Dongdong Chang and
• Xiang Ma

Beilstein J. Org. Chem. 2018, 14, 1994–2001, doi:10.3762/bjoc.14.174

• beginning, which can be detected by high-resolution mass spectrometry (Figure S7, Supporting Information File 1). Then, the dimers and single molecules 3 were able to assemble together through π–π stacking and hydrogen bonding to fabricate the nanofibers. Finally, those fibers twisted with each other to

Water-soluble SNS cationic palladium(II) complexes and their Suzuki–Miyaura cross-coupling reactions in aqueous medium

• Alphonse Fiebor,
• Richard Tia,
• Banothile C. E. Makhubela and
• Henok H. Kinfe

Beilstein J. Org. Chem. 2018, 14, 1859–1870, doi:10.3762/bjoc.14.160

• AgOTf to provide the desired SNS-Pd(II) complex 17a in quantitative yield (Scheme 1). The structure of the complex was established using NMR spectroscopy and high-resolution mass spectrometry. Among others, the downfield shift of all the protons in the complex, when compared to the corresponding protons

Preparation and X-ray structure of 2-iodoxybenzenesulfonic acid (IBS) – a powerful hypervalent iodine(V) oxidant

• Irina A. Mironova,
• Pavel S. Postnikov,
• Rosa Y. Yusubova,
• Akira Yoshimura,
• Thomas Wirth,
• Viktor V. Zhdankin,
• Victor N. Nemykin and
• Mekhman S. Yusubov

Beilstein J. Org. Chem. 2018, 14, 1854–1858, doi:10.3762/bjoc.14.159

• problems, IBS was previously characterized by 1H and 13C NMR, IR spectroscopy, high-resolution mass spectrometry, and elemental analysis. However, all previously reported attempts to grow single crystals of IBS from methanol or acetonitrile resulted in reduction with the formation of 2

Synthesis and photophysical studies of a multivalent photoreactive Ru^II-calix[4]arene complex bearing RGD-containing cyclopentapeptides

• Sofia Kajouj,
• Lionel Marcelis,
• Alice Mattiuzzi,
• Adrien Grassin,
• Damien Dufour,
• Pierre Van Antwerpen,
• Didier Boturyn,
• Eric Defrancq,
• Mathieu Surin,
• Julien De Winter,
• Pascal Gerbaux,
• Ivan Jabin and
• Cécile Moucheron

Beilstein J. Org. Chem. 2018, 14, 1758–1768, doi:10.3762/bjoc.14.150

• the ArH, ArCH2 and OPr group are differentiated. Moreover, complex 7 was also characterized by high-resolution mass spectrometry (HRMS). The ESI mass spectrum displays two intense signals at m/z 764.736 and m/z 1642.456 that are attributed respectively to the doubly charged 72+ and singly charged [7

Hypervalent iodine-guided electrophilic substitution: para-selective substitution across aryl iodonium compounds with benzyl groups

• Cyrus Mowdawalla,
• Faiz Ahmed,
• Tian Li,
• Kiet Pham,
• Loma Dave,
• Grace Kim and
• I. F. Dempsey Hyatt

Beilstein J. Org. Chem. 2018, 14, 1039–1045, doi:10.3762/bjoc.14.91

• . Acknowledgements This research was supported by Faculty Development Grants and a Frederick Bettelheim Research Award from Adelphi University to I. F. Dempsey Hyatt. We are grateful to Dr. Brian Stockman for his NMR expertise and Dr. Daniel A. Todd for acquisition of the high resolution mass spectrometry data at

An uracil-linked hydroxyflavone probe for the recognition of ATP

• Márton Bojtár,
• Péter Zoltán Janzsó-Berend,
• Dávid Mester,
• Dóra Hessz,
• Mihály Kállay,
• Miklós Kubinyi and
• István Bitter

Beilstein J. Org. Chem. 2018, 14, 747–755, doi:10.3762/bjoc.14.63

• alkaline hydrogen peroxide to obtain the clickable fluorophore. All new compounds were characterized by NMR and high-resolution mass spectrometry. Optical spectroscopy The solubility of the UHF probe was very poor in water which resulted in the decrease of fluorescence over time upon dilution from the

AuBr₃-catalyzed azidation of per-O-acetylated and per-O-benzoylated sugars

• Jayashree Rajput,
• Srinivas Hotha and
• Madhuri Vangala

Beilstein J. Org. Chem. 2018, 14, 682–687, doi:10.3762/bjoc.14.56

• and 100 MHz spectrometer, respectively using CDCl3 as the solvent. Chemical shifts (δ) are given in ppm. For perbenzoate compounds 10–15, tetramethyl silane was used as internal standard. Electrospray ionization (ESI) was used for high resolution mass spectrometry (HRMS). An FTIR spectrometer was used

Synthesis and stability of strongly acidic benzamide derivatives

• Frederik Diness,
• Niels J. Bjerrum and
• Mikael Begtrup

Beilstein J. Org. Chem. 2018, 14, 523–530, doi:10.3762/bjoc.14.38

• Bruker 500 MHz spectrometer at 298 K with methanol-d4, DMSO-d6 or hexafluorobenzene as internal standard. High-resolution mass spectrometry (HRMS) was performed on a Bruker MALDI–TOF spectrometer. General procedure Benzoyl chloride (10.0 mmol) in Et2O (10 mL) was added dropwise to a solution of

Synthesis of 1,3-cis-disubstituted sterically encumbered imidazolidinone organocatalysts

• Jan Wallbaum and
• Daniel B. Werz

Beilstein J. Org. Chem. 2017, 13, 2577–2583, doi:10.3762/bjoc.13.254

• were made by combination of H,H-COSY, HSQC, HMBC and NOESY experiments. In some cases signals in the 13C NMR spectrum are missing because of bad relaxation of the respective signals. ESI high-resolution mass spectrometry was carried out on a FTICR instrument. IR spectra were measured on an ATR