Pyridylidene ligand facilitates gold-catalyzed oxidative C–H arylation of heterocycles

• Kazuhiro Hata,
• Hideto Ito,
• Yasutomo Segawa and
• Kenichiro Itami

Beilstein J. Org. Chem. 2015, 11, 2737–2746, doi:10.3762/bjoc.11.295

• PhICl2 (see Experimental section and Supporting Information File 1 for details) [114]. The X-ray crystallographic analysis was successfully accomplished with a colorless single crystal of AuCl3(PyC), which was recrystallized from nitrobenzene and pentane (Figure 3) [115]. The X-ray crystal structure

Inclusion complexes of 2-methoxyestradiol with dimethylated and permethylated β-cyclodextrins: models for cyclodextrin–steroid interaction

• Mino R. Caira,
• Susan A. Bourne,
• Halima Samsodien and
• Vincent J. Smith

Beilstein J. Org. Chem. 2015, 11, 2616–2630, doi:10.3762/bjoc.11.281

• (12.6 ± 0.6 water molecules per complex unit) respectively, and hence the complex formula (β-CD)2·2ME·(12.6 ± 0.6)H2O. X-ray crystal structure solution by isomorphous replacement, using as trial model the host molecule coordinates of KOFJEU, led to successful refinement of the host framework but the

Investigation of the role of stereoelectronic effects in the conformation of piperidones by NMR spectroscopy and X-ray diffraction

• Cesar Garcias-Morales,
• David Ortegón-Reyna and
• Armando Ariza-Castolo

Beilstein J. Org. Chem. 2015, 11, 1973–1984, doi:10.3762/bjoc.11.213

• point matrix of 1024 × 256 with a spectral width of 6354 × 6354 Hz, mixture time of 1 s, and a recycle delay of 1.5 s [66][67]. Mass spectra were recorded on an Agilent G1969 LC/MSD TOF spectrometer coupled to HPLC with electrospray ionization. X-ray crystal structure analysis The crystals were mounted

Fates of imine intermediates in radical cyclizations of N-sulfonylindoles and ene-sulfonamides

• Hanmo Zhang,
• E. Ben Hay,
• Stephen J. Geib and
• Dennis P. Curran

Beilstein J. Org. Chem. 2015, 11, 1649–1655, doi:10.3762/bjoc.11.181

• spectra, and in one case, from an X-ray crystal structure. Assorted bicyclic and tricyclic imines were formed with both spiro-rings and fused-rings and with varying ring sizes and substituents. Extending this work, we have studied radical cyclizations of several ene-sulfonamides and N-sulfonylindoles. The

Pd(OAc)₂-catalyzed dehydrogenative C–H activation: An expedient synthesis of uracil-annulated β-carbolinones

• Biplab Mondal,
• Somjit Hazra,
• Tarun K. Panda and
• Brindaban Roy

Beilstein J. Org. Chem. 2015, 11, 1360–1366, doi:10.3762/bjoc.11.146

• the Pd catalyst between the indole nitrogen and amide carbonyl oxygen. A representative X-ray crystal structure of β-carbolinone derivative 5h was obtained [57] (Figure 2). The inactivity of Pd(0) (Table 1, entry 17), and inferior reactivity of other less electrophilic Pd catalysts indicates a

A new and convenient synthetic way to 2-substituted thieno[2,3-b]indoles

• Roman A. Irgashev,
• Arseny A. Karmatsky,
• Gennady L. Rusinov and
• Valery N. Charushin

Beilstein J. Org. Chem. 2015, 11, 1000–1007, doi:10.3762/bjoc.11.112

• , 1871, 1909, 1936, 1969, 2332, 2736, 2889, 2936, 2974, 2989, 3075, 3058 cm−1; Anal. calcd for C18H14N2O2S: C, 67.06; H, 4.38; N, 8.69; found: C, 66.98; H, 4.35; N, 8.72. Natural and synthetic derivatives of thieno[2,3-b]indole. Mercury [34] representation of the X-ray crystal structure of 12a. Thermal

Tuning the size of a redox-active tetrathiafulvalene-based self-assembled ring

• Sébastien Bivaud,
• Sébastien Goeb,
• Vincent Croué,
• Magali Allain,
• Flavia Pop and
• Marc Sallé

Beilstein J. Org. Chem. 2015, 11, 966–971, doi:10.3762/bjoc.11.108

• -assembly M4L2. For clarity, H atoms and TfO− counteranions have been omitted. 1H NMR, downfield region (α and β signals correspond respectively to α and β pyridyl protons): (a) L1 (DMSO-d6), (b) M4L2 (CD3NO2), (c) M6L3 (DMSO-d6), (d) DOSY NMR of M4L2 (CD3NO2) and (e) DOSY NMR of M6L3 (DMSO-d6). X-ray

• crystal structure of self-assembly M6L3. For clarity, H atoms and TfO− counteranions have been omitted. Geometry (from XRD) around two Pd centers in M4L2 (a) and M6L3 (b). The exTTF moieties have been cut for clarity. Cyclic voltammogram of L1 (c = 10−3 M, CH3CN/CH2Cl2 (v/v 50/50), 0.1 M n-Bu4NPF6, 100

Interactions between tetrathiafulvalene units in dimeric structures – the influence of cyclic cores

• Huixin Jiang,
• Virginia Mazzanti,
• Christian R. Parker,
• Søren Lindbæk Broman,
• Jens Heide Wallberg,
• Karol Lušpai,
• Adam Brincko,
• Henrik G. Kjaergaard,
• Anders Kadziola,
• Peter Rapta,
• Ole Hammerich and
• Mogens Brøndsted Nielsen

Beilstein J. Org. Chem. 2015, 11, 930–948, doi:10.3762/bjoc.11.104

• shortest distance of 6.64 Å according to the X-ray crystal structure [10]. For the other radiaannulene, 8, the first oxidation of each TTF unit was also split into two waves, again indicating interaction between them. In this molecule, the two TTF units are separated by a distance of 6.31 Å. Several bis

• -bis(diphenylphosphino)ethane (dppe) ligands and the Me group on the TFF might restrict the rotation around the triple bond and sterically keep the two TTFs in the same plane as revealed by the X-ray crystal structure [22]. In compound 18, the two TTFs are only separated by a meta-phenylene bridge, but

• supplementary crystallographic data. Bond angles for the cyclic core of 8 (X-ray crystal structure data). Cyclic voltammograms obtained for the oxidation of compounds 1a ([10]), 2a ([10]), and 3b–8 (this work, ca. 1 mM) in CH2Cl2 (0.1 M Bu4NPF6) at a glassy carbon electrode with a scan rate of 0.1 V s−1

Trifluoromethyl-substituted tetrathiafulvalenes

• Olivier Jeannin,
• Frédéric Barrière and
• Marc Fourmigué

Beilstein J. Org. Chem. 2015, 11, 647–658, doi:10.3762/bjoc.11.73

• will be described, based on the X-ray crystal structure analyses of four neutral TTF derivatives, i.e., the EDT-TTF derivatives 2ac and 2bc and the tetrasubstituted derivatives 3bc and 4bc. Redox properties Cyclic voltammetry was used to evaluate the evolution of the donor strength with the nature and

• observed opposite to the CO2Me groups (Table 3), demonstrating again here that the (−M) mesomeric effect of the ester group exercises a stronger effect than the (−I) inductive effect of the CF3 group. Another interesting insight is provided by the X-ray crystal structure of the other isomer 3bc, where each

Synthesis of 1,2-cis-2-C-branched aryl-C-glucosides via desulfurization of carbohydrate based hemithioacetals

• Henok H. Kinfe,
• Fanuel M. Mebrahtu,
• Mandlenkosi M. Manana,
• Kagiso Madumo and
• Mokela S. Sokamisa

Beilstein J. Org. Chem. 2015, 11, 583–588, doi:10.3762/bjoc.11.64

• for the enzymes of Mycobacterium tuberculosis, in particular a deacetylase implicated in the biosynthesis of mycothiol, is under way and the results will be reported in the future. Single X-ray crystal structure of hemithioacetal 3a. (i) CAN, wet silica, KBr, CH2Cl2/CH3CN (1:1), rt, 30 min; (ii) a

Further exploration of the heterocyclic diversity accessible from the allylation chemistry of indigo

• Alireza Shakoori,
• John B. Bremner,
• Mohammed K. Abdel-Hamid,
• Anthony C. Willis,
• Rachada Haritakun and
• Paul A. Keller

Beilstein J. Org. Chem. 2015, 11, 481–492, doi:10.3762/bjoc.11.54

• ring confirmed the presence of the non-alkylated isoindoline moiety. The observation of one set of peaks in the 13C NMR spectrum indicated the presence of a single enantiomeric pair of isomers, and analysis of the X-ray crystal structure (Figure 4) showed that the relative stereochemistry was either

• stereospecific product yields in these one-pot reactions and further studies are continuing. The structure and X-ray crystal structure (ball and stick representation) of azepinodiindolone 7. The corresponding ORTEP data for 7, 8 and 9 is reported in Supporting Information File 1. Dihydroazepino[1,2-a:3,4-b

• view. Right: NOESY correlations in support of the proposed structure (s = strong; w = weak). Structural analysis of compound 23. Left: modelled structure showing the cisoid configuration of the NH and the cinnamyl substituents. Middle: X-ray crystal structure (ball and stick representation) showing the

The reactions of 2-ethoxymethylidene-3-oxo esters and their analogues with 5-aminotetrazole as a way to novel azaheterocycles

• Marina V. Goryaeva,
• Yanina V. Burgart,
• Marina A. Ezhikova,
• Mikhail I. Kodess and
• Viktor I. Saloutin

Beilstein J. Org. Chem. 2015, 11, 385–391, doi:10.3762/bjoc.11.44

• -ray crystal structure of compound 5 (ORTEP drawing, 50% probability level). X-ray crystal structure of compound 11 (ORTEP drawing, 50% probability level). Interaction of 2-ethoxymethylidene-3-oxo esters 1a–c with 5-AT. R = CF3 (a), (CF2)2H (b), Me (c). Conditions, i: TFE, Δ, 32–38 h; ii: Air, rt, 12

• . Thus, we have found an effective and simple reaction for the preparation of substituted pyrimidine and pyridine derivatives. The resulting compounds are important pharmacophores or may be used as a starting material for synthesis of other functionalized pyrimidines through nucleophilic substitution. X

Attempts to prepare an all-carbon indigoid system

• Şeref Yildizhan,
• Henning Hopf and
• Peter G. Jones

Beilstein J. Org. Chem. 2015, 11, 363–372, doi:10.3762/bjoc.11.42

• not the hoped-for diene 22, but an isomer, the hydrocarbon 23 (Scheme 5). The structure of hydrocarbon 23 was established by the usual spectroscopic data (see experimental section) and also by an X-ray crystal structure determination (Figure 3). The molecule of 23 is planar (mean deviation 0.03 Å) and

An unusually stable chlorophosphite: What makes BIFOP–Cl so robust against hydrolysis?

• Roberto Blanco Trillo,
• Jörg M. Neudörfl and
• Bernd Goldfuss

Beilstein J. Org. Chem. 2015, 11, 313–322, doi:10.3762/bjoc.11.36

• after 37 min forming 7 (cf. Scheme 2 and Scheme 3). The integration values are shown below the signals. X-ray crystal structure of diphenyl ether-2,2’-biscyclofenchene 7. Ellipsoids are shown with 50% probability. 31P NMR (125 MHz, CDCl3) of O–BIFOP–H (4, δ = 152.5) adding O2 after a) 5 min; b) 15 min

• ; c) 120 min; d) adding 1 equiv H2O forming O-BIFOP-(O)H (6, δ = −8.2). X-ray crystal structure of BIFOP-Cl 1. Ellipsoids are shown with 50% probability [15]. X-ray crystal structure of O-BIFOP-Cl (3). Ellipsoids are shown with 50% probability. Transition state structure for the reaction of BIFOP–Cl

Azirinium ylides from α-diazoketones and 2H-azirines on the route to 2H-1,4-oxazines: three-membered ring opening vs 1,5-cyclization

• Nikolai V. Rostovskii,
• Mikhail S. Novikov,
• Alexander F. Khlebnikov,
• Galina L. Starova and
• Margarita S. Avdontseva

Beilstein J. Org. Chem. 2015, 11, 302–312, doi:10.3762/bjoc.11.35

• -azabuta-1,3-dienes which transform back to the oxazines in the dark at room temperature. The rate of the reverse cyclization reaction increases with increasing electron-withdrawing ability of C1-substituent in 2-azabuta-1,3-diene. X-ray crystal structure of azadiene 3e. X-ray crystal structures of

• compounds 6f and 7h. Energy profiles [DFT B3LYP/6-31+G(d,p), 357 K, 1,2-dichloroethane (PCM)] for the transformation of ylide 9j into azadiene 3j and dihydroazireno[2,1-b]oxazole 10j and for the transformation of 10j to adducts 6j,7j. X-ray crystal structure of compound 17. Rh(II)-catalyzed synthesis of

Synthesis of dinucleoside acylphosphonites by phosphonodiamidite chemistry and investigation of phosphorus epimerization

• William H. Hersh

Beilstein J. Org. Chem. 2015, 11, 184–191, doi:10.3762/bjoc.11.19

• was immediately oxidized to give the phosphonoformate dinucleoside. In this paper we report: (1) a more general synthesis of acyl diamidites, which most likely accounts for Caruthers’ results, including the X-ray crystal structure of the benzoyl analog, (2) the diamidite conversion to dinucleoside

• strong carbonyl band in the infrared spectrum at 1631 cm−1. X-ray crystal structure of 9. Large crystals of 9 could be obtained from hexane, allowing confirmation of the structure by single-crystal X-ray diffraction [51]. An ORTEP drawing is shown in Figure 2, illustrating the steric crowding around

Three-component synthesis of C₂F₅-substituted pyrazoles from C₂F₅CH₂NH₂·HCl, NaNO₂ and electron-deficient alkynes

• Pavel K. Mykhailiuk

Beilstein J. Org. Chem. 2015, 11, 16–24, doi:10.3762/bjoc.11.3

• the target products 20b, 21a/b in good yields. Substrate 22 with the second EDG – aryl – did not react, however. Structures of compounds 10a, 19b, 20b were confirmed by X-ray crystal structure analysis (Figure 3) [50]. Reaction regioselectivity Monosubstituted alkynes 1–12 regioselectively reacted

• layer was separated. The aqueous layer was washed with CH2Cl2 (2 × 3 mL). The combined organic layers were dried over Na2SO4 and evaporated under vacuum to provide the pure product. Bioactive compounds and agrochemicals with fluorinated pyrazoles. Bioactive compounds with C2F5 group [34][35][36]. X-ray

• crystal structure of pyrazoles 10a, 19b and 20b [50]. Structure of the expected product 19a, and the observed isomeric one – 19b. Comparison of CF3CHN2 vs C2F5CHN2 in the reaction with alkyne 19. Synthesis of 3,4-disubstituted pyrazole 24. Synthesis of C2F5-substituted acids 25 and 27. In brackets are the

Superoxide chemistry revisited: synthesis of tetrachloro-substituted methylenenortricyclenes

• Basavaraj M. Budanur and
• Faiz Ahmed Khan

Beilstein J. Org. Chem. 2014, 10, 2531–2538, doi:10.3762/bjoc.10.264

• . The studies towards further synthetic applications of KO2 are currently underway in our lab. X-ray crystal structure of 5a with 30% thermal ellipsoids. X-ray crystal structure of 8a with 30% thermal ellipsoids. Synthesis of Nortricyclenes from Norbornenes. KO2-mediated synthesis of tetrachloro

Derivatives of the triaminoguanidinium ion, 3. Multiple N-functionalization of the triaminoguanidinium ion with isocyanates and isothiocyanates

• Jan Szabo,
• Kerstin Karger,
• Nicolas Bucher and
• Gerhard Maas

Beilstein J. Org. Chem. 2014, 10, 2255–2262, doi:10.3762/bjoc.10.234

• Supporting Information File 578: Experimental procedures, characterization data for synthesized compounds, and data for the X-ray crystal structure determinations. Acknowledgements We thank Bernhard Müller (Institute of Inorganic Chemistry II) for the X-ray crystal data collection and Dr. Markus Wunderlin

Scalable synthesis of 5,11-diethynylated indeno[1,2-b]fluorene-6,12-diones and exploration of their solid state packing

• Bradley D. Rose,
• Peter J. Santa Maria,
• Aaron G. Fix,
• Chris L. Vonnegut,
• Lev N. Zakharov,
• Sean R. Parkin and
• Michael M. Haley

Beilstein J. Org. Chem. 2014, 10, 2122–2130, doi:10.3762/bjoc.10.219

• utilized 3 – while the solid-state structure of 3 showed several sub-van der Waals contact distances, the n-type mobility of the OFET was very low (2 × 10−5 cm2 V−1 s−1) [14]. On the other hand, an OFET utilizing 4 (X = F) had measured electron mobilities of 0.17 cm2 V−1 s−1, and its X-ray crystal

• structure revealed 1-dimensional π-stacking with a close interplanar distance of 3.30 Å [15]. Due to the inherent insolubility of compounds 3 and 4, however, they needed to be vapor deposited under vacuum. More recently IF-diones 5–7 were reported (along with polymeric and other derivatives) with 5 and 6

Chiral phosphines in nucleophilic organocatalysis

• Yumei Xiao,
• Zhanhu Sun,
• Hongchao Guo and
• Ohyun Kwon

Beilstein J. Org. Chem. 2014, 10, 2089–2121, doi:10.3762/bjoc.10.218

• the optimal catalyst. Based on the X-ray crystal structure of the catalyst, they proposed that the chiral microenvironment of the binaphthyl-based phosphepine was amplified by its 3,3´-diphenyl substituents. In the presence of the chiral phosphepine B4, the reactions of allenes with electron-deficient

Palladium-catalysed cyclisation of alkenols: Synthesis of oxaheterocycles as core intermediates of natural compounds

• Miroslav Palík,
• Jozef Kožíšek,
• Peter Koóš and
• Tibor Gracza

Beilstein J. Org. Chem. 2014, 10, 2077–2086, doi:10.3762/bjoc.10.216

• and 13C NMR spectra of selected compounds. Supporting Information File 406: X-ray crystal structure analysis of 53. Acknowledgements This work was supported by Slovak Grant Agencies (VEGA No. 1/0488/14, APVV-0203-10, LPP-0071-09 and ASFU, Bratislava, ITMS projects No. 26240120001, 26240120025).

Amino acid motifs in natural products: synthesis of O-acylated derivatives of (2S,3S)-3-hydroxyleucine

• Oliver Ries,
• Martin Büschleb,
• Markus Granitzka,
• Dietmar Stalke and
• Christian Ducho

Beilstein J. Org. Chem. 2014, 10, 1135–1142, doi:10.3762/bjoc.10.113

• neither 4 nor 5 gave crystals suitable for X-ray analysis, the 3-hydroxy group of 4 was acylated with levulinic acid, leading to ester 6 in 82% yield (Scheme 1) which crystallized upon removal of residual solvent under reduced pressure. Hence, a single crystal of 6 was obtained, and X-ray crystal

• structure analysis unambiguously confirmed the relative configuration (Figure 2; see Supporting Information File 1 for crystallographic data). Levulinyl ester 6 crystallizes in the orthorhombic space group P212121 with one molecule in the asymmetric unit. The Flack parameter [35] refined to x = −0.05(8) and

Site-selective covalent functionalization at interior carbon atoms and on the rim of circumtrindene, a C₃₆H₁₂ open geodesic polyarene

• Hee Yeon Cho,
• Ronald B. M. Ansems and
• Lawrence T. Scott

Beilstein J. Org. Chem. 2014, 10, 956–968, doi:10.3762/bjoc.10.94

• [50] the X-ray crystal structure of circumtrindene (6) confirms that the carbon atoms comprising the top of the dome are distorted from planarity to an even greater degree than the carbon atoms in C60 [51]; the pyramidalization in circumtrindene (POAV angle = 12.1° [52], Figure 5) significantly

Columnar/herringbone dual crystal packing of pyrenylsumanene and its photophysical properties

• Binod Babu Shrestha,
• Shuhei Higashibayashi and
• Hidehiro Sakurai

Beilstein J. Org. Chem. 2014, 10, 841–847, doi:10.3762/bjoc.10.80

• ) unidirectional and (b) opposite structures, in addition to (c) the herringbone packing structure typical of planar π-conjugated compounds. The X-ray crystal structure of 1, showing: (a) top view of the ORTEP drawing with 50% probability, b) side view, c) top view of the packing structure with the sumanene bowl