A promising cellulose-based polyzwitterion with pH-sensitive charges

• Thomas Elschner and
• Thomas Heinze

Beilstein J. Org. Chem. 2014, 10, 1549–1556, doi:10.3762/bjoc.10.159

• orthogonal removal of protecting groups. While IR spectroscopy could not proof the presence of all functional groups, the molecular structure was clearly described by NMR spectroscopy. Potentiometric titration (pH), nephelometry, rheology and dynamic light-scattering revealed physicochemical characteristics

Tuning the interactions between electron spins in fullerene-based triad systems

• Maria A. Lebedeva,
• Thomas W. Chamberlain,
• E. Stephen Davies,
• Bradley E. Thomas,
• Martin Schröder and
• Andrei N. Khlobystov

Beilstein J. Org. Chem. 2014, 10, 332–343, doi:10.3762/bjoc.10.31

• solubility, but MALDI–MS (m/z 821) and IR spectroscopy (carbonyl stretch at 1733 cm−1) confirm the assigned structure. The dicyclohexylcarbodiimide (DCC) assisted acid–amine coupling reaction between 15 and [70]fulleropyrrolidine 10 resulted in the formation of the desired asymmetric triad 5, which displayed

Synthesis of five- and six-membered cyclic organic peroxides: Key transformations into peroxide ring-retaining products

• Alexander O. Terent'ev,
• Dmitry A. Borisov,
• Vera A. Vil’ and
• Valery M. Dembitsky

Beilstein J. Org. Chem. 2014, 10, 34–114, doi:10.3762/bjoc.10.6

• (DCA) as the sensitizer [242]. After irradiation of diazene 34 in an argon matrix at 10 K, biradical 35 was detected by IR spectroscopy and the reaction of the latter with oxygen at 10 K proceeded regioselectively to give dioxolane 36 (Scheme 12) [243]. Bicyclic peroxide 2-heptyl-3,4-dioxabicyclo[3.3.0

N,N'-(Hexane-1,6-diyl)bis(4-methyl-N-(oxiran-2-ylmethyl)benzenesulfonamide): Synthesis via cyclodextrin mediated N-alkylation in aqueous solution and further Prilezhaev epoxidation

• Julian Fischer,
• Simon Millan and
• Helmut Ritter

Beilstein J. Org. Chem. 2013, 9, 2834–2840, doi:10.3762/bjoc.9.318

• are relatively comparable to a mixture of BADGE with 8, whereby the observed differences can be caused by different reactivity of the oxirane moieties or unequal solubility of the respective diepoxide with 8. By means of IR spectroscopy, ring opening polymerization of epoxides with amines can be

3-Pyridinols and 5-pyrimidinols: Tailor-made for use in synergistic radical-trapping co-antioxidant systems

• Luca Valgimigli,
• Daniele Bartolomei,
• Riccardo Amorati,
• Evan Haidasz,
• Jason J. Hanthorn,
• Susheel J. Nara,
• Johan Brinkhorst and
• Derek A. Pratt

Beilstein J. Org. Chem. 2013, 9, 2781–2792, doi:10.3762/bjoc.9.313

• solvents of different HBA ability [30]: acetonitrile ( = 0.44), ethyl acetate ( = 0.45), and dimethyl sulfoxide ( = 0.78) using IR spectroscopy [25]. Representative results are shown in Figure 2. Addition of a HBA solvent to solutions of the pyri(mi)dinols in non-H-bonding CCl4 resulted in the progressive

Studies on the photodegradation of red, green and blue phosphorescent OLED emitters

• Susanna Schmidbauer,
• Andreas Hohenleutner and
• Burkhard König

Beilstein J. Org. Chem. 2013, 9, 2088–2096, doi:10.3762/bjoc.9.245

• accompanied by the formation of only one visible degradation product with a mass of 712 (MH+ + 14). This species was attributed to the aldehyde functionalized complex derivative (V, Figure 8b), as the carbonyl functionality was confirmed by NMR spectroscopy with a signal at 10.5 ppm as well as IR spectroscopy

Linkage of α-cyclodextrin-terminated poly(dimethylsiloxanes) by inclusion of quasi bifunctional ferrocene

• Helmut Ritter,
• Berit Knudsen and
• Valerij Durnev

Beilstein J. Org. Chem. 2013, 9, 1278–1284, doi:10.3762/bjoc.9.144

• of 1H NMR and IR spectroscopy and by mass spectrometry. Electron microscopy studies and dynamic light scattering measurements show a significant decrease of the derivative size after the complexation with ferrocene. In addition, further evidence for the successful complexation of the end groups was

• -deoxy)-peracetylated-α-CD (3) using a short-chain oligo(dimethylsiloxane) 1 or a long-chain poly(dimethylsiloxane) 2, respectively, (Scheme 1). During the reactions, samples were collected and investigated by IR spectroscopy in order to ensure the full conversion of the reactants to products (Figure 1

Aqueous reductive amination using a dendritic metal catalyst in a dialysis bag

• Jorgen S. Willemsen,
• Jan C. M. van Hest and
• Floris P. J. T. Rutjes

Beilstein J. Org. Chem. 2013, 9, 960–965, doi:10.3762/bjoc.9.110

• the addition of pyridine to quench the excess of tricarbonate 11, ligand 8 was added, leading to the formation of dendrimers 12 and 13 in good yields. The products were completely characterized by 1H and 13C NMR, thereby confirming that all amines had been reacted. Furthermore, IR spectroscopy showed

3D-printed devices for continuous-flow organic chemistry

• Vincenza Dragone,
• Victor Sans,
• Mali H. Rosnes,
• Philip J. Kitson and
• Leroy Cronin

Beilstein J. Org. Chem. 2013, 9, 951–959, doi:10.3762/bjoc.9.109

• reactionware has been demonstrated by studying and optimizing the residence time to synthesize a range of imines and secondary amines and to monitor the reactions in real time using in-line IR spectroscopy. These robust, inexpensive and chemically inert 3D-printed reactors have proven suitable vessels for

Superstructures of fluorescent cyclodextrin via click-reaction

• Arkadius Maciollek,
• Helmut Ritter and
• Rainer Beckert

Beilstein J. Org. Chem. 2013, 9, 827–831, doi:10.3762/bjoc.9.94

• and Discussion The water-soluble fluorescent cyclodextrin was synthesized via copper-catalyzed cycloaddition (Scheme 1). The existence of the resulting product was confirmed by MALDI–TOF spectrometry, 1H NMR and IR spectroscopy. The formation of host–guest structures between the thiazole functionality

4-Pyridylnitrene and 2-pyrazinylcarbene

• Curt Wentrup,
• Ales Reisinger and
• David Kvaskoff

Beilstein J. Org. Chem. 2013, 9, 754–760, doi:10.3762/bjoc.9.85

• ) or triazole 24 in an Ar matrix at 7–10 K causes efficient ring expansion to the cyclic seven-membered ring ketenimine 20 as observed by IR spectroscopy (Figure 2). In the case of triazole 24, efficient ring opening to the diazo compound 22 happens first (Figure 1), so the latter is the immediate

• IR spectroscopy. FVT products were isolated in liquid nitrogen (77 K) in the preparative thermolyses, and at 22–25 K in Ar matrices for IR experiments. IR spectra of the Ar matrices were measured at 7–10 K with a resolution of 1 cm−1. Photolyses were done through quartz by using a 75 W low-pressure

• ’-Azopyridine (25) (54% yield; red solid, mp 107–108 °C) was identified by comparison with a sample prepared according to den Hertog et al. (mp 107.5 °C) [22]. Traces of unreacted azide 18 and 2- and 3-cyanopyrroles 16 and 17were detected by GC–MS and IR spectroscopy. “Violent pyrolysis” was achieved by holding

3-Pyridylnitrene, 2- and 4-pyrimidinylcarbenes, 3-quinolylnitrenes, and 4-quinazolinylcarbenes. Interconversion, ring expansion to diazacycloheptatetraenes, ring opening to nitrile ylides, and ring contraction to cyanopyrroles and cyanoindoles

• Curt Wentrup,
• Nguyen Mong Lan,
• Adelheid Lukosch,
• Pawel Bednarek and
• David Kvaskoff

Beilstein J. Org. Chem. 2013, 9, 743–753, doi:10.3762/bjoc.9.84

• ] were as previously described. KBr and CsI windows were used for IR spectroscopy. FVT products were isolated in liquid nitrogen (77 K) in the preparative thermolysis, and at 22–25 K in Ar matrices for IR experiments. IR spectra of the Ar matrices were measured at 7–10 K with a resolution of 1 cm−1

• –700 °C the products of FVT were condensed on a KBr window at 77 K for IR spectroscopy. In each case the product was a mixture of 3-cyano-2-phenylindole and indolo[3,2-b]quinoline according to IR spectroscopy of the crude and TLC of the isolated material. Thermolysis of 3-azido-2-phenylquinoline (44

• similar experiments with FVT at 600–800 °C the product was isolated on a KBr window at 77 K for IR spectroscopy. In each case 3-cyano-2-phenylindole (48) was the exclusive product. Thermolysis of 2-phenyl-4-(5-tetrazolyl)quinazoline (52) in solution: (a) A solution of 250 mg (0.91 mmol) in 50 mL of xylene

End-labeled amino terminated monotelechelic glycopolymers generated by ROMP and Cu(I)-catalyzed azide–alkyne cycloaddition

• Ronald Okoth and
• Amit Basu

Beilstein J. Org. Chem. 2013, 9, 608–612, doi:10.3762/bjoc.9.66

• terminal alkyne [20][21]. For our purposes the later method was attractive as we could follow the reaction by monitoring the disappearance of the azide asymmetric stretch at 2100 cm−1 by IR spectroscopy. As shown in Scheme 1, reaction of the ROMP polymer 6 with excess amino–azide linker 8 [22] (2

Reactions of nitroxides XIII: Synthesis of the Morita–Baylis–Hillman adducts bearing a nitroxyl moiety using 4-acryloyloxy-2,2,6,6-tetramethylpiperidine-1-oxyl as a starting compound, and DABCO and quinuclidine as catalysts

• Jerzy Zakrzewski

Beilstein J. Org. Chem. 2012, 8, 1515–1522, doi:10.3762/bjoc.8.171

• TLC, resulted in the separation of the expected adduct 5o in 2% yield. However, its identity was confirmed unambiguously by (HR-)MS (both EI and ESI) and IR spectroscopy. This poor result is probably caused by the cumulative steric hindrance of both ferrocenyl and nitroxyl moieties (the sensitivity of

• the MBH reaction to the steric hindrance of the alcohol moiety in an acrylate was commented on in the introduction [20][45]). Due to the radical nature of the adducts 5a–o, their structures were confirmed by (HR-)MS (both EI and ESI), and IR spectroscopy (see Supporting Information File 1 for EIMS and

Synthesis and characterization of low-molecular-weight π-conjugated polymers covered by persilylated β-cyclodextrin

• Aurica Farcas,
• Ana-Maria Resmerita,
• Andreea Stefanache,
• Mihaela Balan and
• Valeria Harabagiu

Beilstein J. Org. Chem. 2012, 8, 1505–1514, doi:10.3762/bjoc.8.170

• chemical structure and the thermal and morphological properties of the resulting polyrotaxane were investigated by using NMR and FT-IR spectroscopy, TGA, DSC and AFM analysis. The encapsulation of BT inside the PS-βCD cavity results in improvements in the solubility, as well as in different surface

Cyanoethylation of the glucans dextran and pullulan: Substitution pattern and formation of nanostructures and entrapment of magnetic nanoparticles

• Kathrin Fiege,
• Heinrich Lünsdorf,
• Sevil Atarijabarzadeh and
• Petra Mischnick

Beilstein J. Org. Chem. 2012, 8, 551–566, doi:10.3762/bjoc.8.63

• obtained by Michael addition of acrylonitrile to the glucans under various conditions. Products were thoroughly characterized, comprising elementary analysis, NMR and ATR–IR spectroscopy, and analysis of the substituent distribution in the glucosyl units by GC–FID and GC–MS of the constituting

• structural characterization of the material. Cyanoethylation is established for polysaccharides, but the substituent pattern has only been studied for cyanoethylamylose and starch [3]. In most cases, the products have only been roughly characterized by NMR and IR spectroscopy or by elementary analysis [1][2

• . Results are given in Table 1. DSEA(C/N) was 0 to 7.8% higher than DSEA(N). In the following the functionalized glucans were investigated by ATR–IR spectroscopy. The characteristic C≡N stretching vibration was detected at 2250 cm−1 increasing with DS, while the intensity of the OH stretching (3400 cm−1

Synthesis of mesomeric betaine compounds with imidazolium-enolate structure

• Nina Gonsior,
• Fabian Mohr and
• Helmut Ritter

Beilstein J. Org. Chem. 2012, 8, 390–397, doi:10.3762/bjoc.8.42

• 10.3762/bjoc.8.42 Abstract The synthesis of a heterocyclic mesomeric betaine by quaternization reaction of 1-butylimidazole and tetrabromo-1,4-benzoquinone is presented. The structure was verified by means of X-ray single-crystal analysis, NMR and IR spectroscopy. Inclusion complexes of the heterocyclic

• and IR spectroscopy, as well as X-ray single-crystal analysis. The 1H NMR spectrum of 3 is depicted in Figure 1. The signals for all structural features were found, e.g., at 9.21 ppm, 7.81 ppm and 7.64 ppm, for the imidazolium protons, and in the range of 4.23–0.92 ppm for the butyl moiety

• -1H-imidazole and tetrabromo-1,4-benzoquinone was presented. The structure was verified by means of X-ray single-crystal analysis, as well as NMR and IR spectroscopy. Furthermore, mesoion 3 was classified by the comprehensive classification system for heterocyclic mesomeric betaines, as a conjugated

Continuous-flow catalytic asymmetric hydrogenations: Reaction optimization using FTIR inline analysis

• Magnus Rueping,
• Teerawut Bootwicha and
• Erli Sugiono

Beilstein J. Org. Chem. 2012, 8, 300–307, doi:10.3762/bjoc.8.32

• : asymmetric reduction; binolphosphoric acid; Brønsted acid; Hantzsch dihydropyridine; IR spectroscopy; real-time analysis; Introduction In recent years, a growing interest in microreactor technology has been seen in the scientific community and the development of microfabricated reaction systems is actively

• temperature for the asymmetric continuous-flow reduction, a temperature profile was recorded. The reaction temperature was initially 5 °C and was increased to 60 °C over a period of 8 h, while the conversion was monitored by inline IR-spectroscopy. Figure 1a shows the real-time plot of the peak intensity

Imidazole as a parent π-conjugated backbone in charge-transfer chromophores

• Jiří Kulhánek and
• Filip Bureš

Beilstein J. Org. Chem. 2012, 8, 25–49, doi:10.3762/bjoc.8.4

• ]). These chromophores were synthesized by Debus–Radziszewski synthesis (Scheme 1), as two series of compounds with different acceptors A (NO2 or CN groups), and were investigated by electrochemistry, UV–vis and IR spectroscopy (CN), and quantum-chemical calculations (Table 5). Considering all the above

Miniemulsion polymerization as a versatile tool for the synthesis of functionalized polymers

• Daniel Crespy and
• Katharina Landfester

Beilstein J. Org. Chem. 2010, 6, 1132–1148, doi:10.3762/bjoc.6.130

• distribution when the monomers were polymerized by γ-rays compared to initiation with potassium peroxodisulfate. The presence of carboxylic acid groups at the surface of the particles was confirmed by X-ray photoelectron and FT-IR spectroscopy. Finally, graft hybrid copolymers of polyurethane and polymers from

Formation of epoxide-amine oligo-adducts as OH-functionalized initiators for the ring-opening polymerization of ε-caprolactone

• Julia Theis and
• Helmut Ritter

Beilstein J. Org. Chem. 2010, 6, 938–944, doi:10.3762/bjoc.6.105

• reaction was carried out under simultaneous cooling with 5 psi of compressed air. The obtained epoxide-amine addition product 4 was characterized by 13C NMR, Fourier transform infrared (FT-IR) spectroscopy and matrix-assisted laser desorption-ionization time-of-flight (MALDI-TOF) mass spectrometry. The

• successful reduction of the nitroaromatic compound 2 was proven by IR spectroscopy by the disappearance of the asymmetric and symmetric NO2 stretching vibration absorption bands at 1589 and 1329 cm−1, respectively. The addition reaction of the new formed primary aromatic amine 3 with diepoxide 1 was proven

• by bismuth(III) trifluoromethanesulfonate, which is known as effective catalyst for ROP [27] (Scheme 2). The dilution of the hydroxy groups in the obtained product 6 was proven by IR spectroscopy by the nearly complete disappearance of the OH-related absorption band at 3370 cm−1. Furthermore, the

Hybrid biofunctional nanostructures as stimuli-responsive catalytic systems

• Gernot U. Marten,
• Thorsten Gelbrich and
• Annette M. Schmidt

Beilstein J. Org. Chem. 2010, 6, 922–931, doi:10.3762/bjoc.6.98

• ATRP is qualitatively analyzed by transmission electron microscopy (TEM) and ATR-IR spectroscopy [33] on carefully washed and dried particles. TEM images (Figure 2) of the obtained nanoparticles demonstrate strongly contrasting Fe3O4 cores surrounded by less contrasting polymer shells. The nearly

Calix[4]arene-click-cyclodextrin and supramolecular structures with watersoluble NIPAAM-copolymers bearing adamantyl units: “Rings on ring on chain”

• Bernd Garska,
• Monir Tabatabai and
• Helmut Ritter

Beilstein J. Org. Chem. 2010, 6, 784–788, doi:10.3762/bjoc.6.83

• 5,11,17,23-tetra-tert-butyl-25,27-dipropargylether-26,28-hydroxy-calix[4]arene (calix[4]arene-dipropargylether) (2) onto 6I-azido-6I-deoxycyclomaltoheptaose (3) under microwave assisted conditions. The coupling was proven by MALDI-TOF mass spectrometry, 1H NMR and IR-spectroscopy. The pH dependent

• -dipropargylether-26,28-hydroxy-calix[4]arene (calix[4]arene-1,3-dipropargylether) (2) onto 6I-azido-6I-deoxycyclomaltoheptaose (3) was proven by IR spectroscopy by the disappearance of the bands for the azide group at 2105 cm−1 and for the propargyl group at 2115 cm−1, whilst the formation of the triazole ring was

Synthesis of some novel hydrazono acyclic nucleoside analogues

• Mohammad N. Soltani Rad,
• Ali Khalafi-Nezhad and
• Somayeh Behrouz

Beilstein J. Org. Chem. 2010, 6, No. 49, doi:10.3762/bjoc.6.49

• %). Moreover, N-benzyl adenine derivative 1o was obtained as the N(9)-isomer in 76% yield, while theophylline was mostly alkylated at N(7) to afford 1m (69%). All compounds were fully characterized and their structures confirmed by 1H and 13C NMR, elemental analysis, mass and IR spectroscopy. Although

Synthesis of bis(3-{[2-(allyloxy)ethoxy]methyl}-2,4,6-trimethylbenzoyl)(phenyl)phosphine oxide – a tailor-made photoinitiator for dental adhesives

• Norbert Moszner,
• Iris Lamparth,
• Jörg Angermann,
• Urs Karl Fischer,
• Frank Zeuner,
• Thorsten Bock,
• Robert Liska and
• Volker Rheinberger

Beilstein J. Org. Chem. 2010, 6, No. 26, doi:10.3762/bjoc.6.26

• )ethoxy]methyl}-2,4,6-trimethylbenzoyl)(phenyl)phosphine, which was oxidized to WBAPO. The structure of WBAPO was confirmed by 1H NMR, 13C NMR, 31P NMR, and IR spectroscopy, as well as elemental analysis. WBAPO, a yellow liquid, possesses improved solubility in polar solvents and shows UV–vis absorption

• chromatography, WBAPO was obtained as a yellow oil in 67% yield with a HPLC purity of 94–95%. The characterization of WBAPO was carried out by 1H NMR, 13C NMR, 31P NMR and IR spectroscopy, as well as by elemental analysis. The spectral data are in agreement with the expected structure. For example, the presence