Coordination chemistry and photoswitching of dinuclear macrocyclic cadmium-, nickel-, and zinc complexes containing azobenzene carboxylato co-ligands

• Jennifer Klose,
• Tobias Severin,
• Peter Hahn,
• Alexander Jeremies,
• Jens Bergmann,
• Daniel Fuhrmann,
• Jan Griebel,
• Bernd Abel and
• Berthold Kersting

Beilstein J. Org. Chem. 2019, 15, 840–851, doi:10.3762/bjoc.15.81

• ·8EtOH (7·8EtOH). Only one orientation of the disordered azo-carboxylato co-ligand is displayed. Hydrogen atoms omitted for clarity. Thermal ellipsoids are drawn at the 50% probability level. Left: ORTEP representation of the molecular structure of the [Cd2L(μ-azo-CO2Me)]+ cation in crystals of 8·MeCN

Catalyst-free assembly of giant tris(heteroaryl)methanes: synthesis of novel pharmacophoric triads and model sterically crowded tris(heteroaryl/aryl)methyl cation salts

• Rodrigo Abonia,
• Luisa F. Gutiérrez,
• Braulio Insuasty,
• Jairo Quiroga,
• Kenneth K. Laali,
• Chunqing Zhao,
• Gabriela L. Borosky,
• Samantha M. Horwitz and
• Scott D. Bunge

Beilstein J. Org. Chem. 2019, 15, 642–654, doi:10.3762/bjoc.15.60

• reactions could also be carried out in water (at circa 80 °C) but with chemoselectivity favoring (Ar1Ar1Ar2)CH over (Ar1Ar2Ar3)CH. The molecular structure of a representative (Ar1Ar2Ar3)CH triad was confirmed by X-ray analysis. Model tris(heteroaryl/aryl)methylium salts were generated by reaction with DDQ

Synthesis of a tubugi-1-toxin conjugate by a modulizable disulfide linker system with a neuropeptide Y analogue showing selectivity for hY1R-overexpressing tumor cells

• Rainer Kufka,
• Robert Rennert,
• Goran N. Kaluđerović,
• Lutz Weber,
• Wolfgang Richter and
• Ludger A. Wessjohann

Beilstein J. Org. Chem. 2019, 15, 96–105, doi:10.3762/bjoc.15.11

• targeting of the conjugate towards a specific molecular structure that has been identified to be characteristic for a diseased state of cells and tissues. Particularly G protein-coupled receptors (GPCRs) that are endogenously activated by agonistic peptide or protein ligands can be suitable target

N-Arylphenothiazines as strong donors for photoredox catalysis – pushing the frontiers of nucleophilic addition of alcohols to alkenes

• Fabienne Speck,
• David Rombach and
• Hans-Achim Wagenknecht

Beilstein J. Org. Chem. 2019, 15, 52–59, doi:10.3762/bjoc.15.5

• reduction potential interestingly is higher than in the parent compound 1 although there are electron-donating alkyl groups present in the molecular structure. This can be explained by a twist of the arene moieties due to steric bulk causing an interruption of the delocalization. The electron transfer is

1,8-Bis(dimethylamino)naphthyl-2-ketimines: Inside vs outside protonation

• A. S. Antonov,
• A. F. Pozharskii,
• P. M. Tolstoy,
• A. Filarowski and
• O. V. Khoroshilova

Beilstein J. Org. Chem. 2018, 14, 2940–2948, doi:10.3762/bjoc.14.273

• case, we were able to experimentally observe the simultaneous out-inversion and protonation of the 1-NMe2 group for the first time. C=NH Signal regions of temperature-depending 1H NMR spectra for compounds 4a–7a, acetone-d6. Molecular structure of imines 6a (a) and 4a (b). The H···O distance for 6a is

• ΔE = Eb’ – Eb (kcal/mol) for different sites of protonation of the studied imines (B3LYP/6-311+G(d,p)). Molecular structure of protonated imines 4a·HClO4 (a) and 6b·EtOH (b). C=NH2+ Signal regions of temperature-depending spectra for compounds 4c–7c, acetone-d6. Molecular structure of dication 6с

Oxidative and reductive cyclization in stiff dithienylethenes

• Michael Kleinwächter,
• Ellen Teichmann,
• Lutz Grubert,
• Martin Herder and
• Stefan Hecht

Beilstein J. Org. Chem. 2018, 14, 2812–2821, doi:10.3762/bjoc.14.259

• [5][6][7][8][9][10][11][12][13] or cycloreversion [14][15][16][17][18][19][20][21] can be observed, while correlation of both reaction modes to the molecular structure is still under discussion [22][23][24][25][26]. There are only few reports about reductive isomerization, each involving the ionic

Molecular iodine-catalyzed one-pot multicomponent synthesis of 5-amino-4-(arylselanyl)-1H-pyrazoles

• Camila S. Pires,
• Daniela H. de Oliveira,
• Maria R. B. Pontel,
• Jean C. Kazmierczak,
• Roberta Cargnelutti,
• Diego Alves,
• Raquel G. Jacob and
• Ricardo F. Schumacher

Beilstein J. Org. Chem. 2018, 14, 2789–2798, doi:10.3762/bjoc.14.256

• copper salt. To confirm the structure of 6, its molecular structure was also analyzed by single-crystal X-ray diffraction (CCDC: 1853770). The molecular structure is demonstrated in Figure 1. Conclusion A variety of 4-(arylselanyl)-1H-pyrazol-5-amines was prepared in a one-pot multicomponent procedure

• . Molecular structure of compound 6. The hydrogen atoms are omitted for clarity [27]. Synthesis of selanyl-pyrazoles and their derivatives previously described. Multicomponent reaction proposed in this work. Direct selanylation reaction of 5-amino-pyrazole 5a with diphenyl diselenide (3a) under the optimized

Transition metal-free oxidative and deoxygenative C–H/C–Li cross-couplings of 2H-imidazole 1-oxides with carboranyl lithium as an efficient synthetic approach to azaheterocyclic carboranes

• Lidia A. Smyshliaeva,
• Mikhail V. Varaksin,
• Pavel A. Slepukhin,
• Oleg N. Chupakhin and
• Valery N. Charushin

Beilstein J. Org. Chem. 2018, 14, 2618–2626, doi:10.3762/bjoc.14.240

• -(4-bromophenyl)-2-ethyl-2-methyl-1-oxido-2H-imidazol-5-yl)-1,2-dicarba-closo-dodecaborane (5d) in CDCl3 at 295 K. Fragment of the 2D 1H–13C{1H} HSQC (a) and HMBC (b) spectra of imidazolyl carborane 5d in CDCl3 at 295 K (the whole spectra are shown in Supporting Information File 1). Molecular

• structure of 5d. Selected bond distances (Å) and angles (deg) for molecule 1: C(3)–C(14), 1.665; C(3)–C(5), 1.491; C(5)–N(1), 1.338; C(5)–C(4), 1.472; Br(1)–C(9), 1.910; O(1)–N(1), 1.281; N(3)–C(4), 1.30; N(3)–C(2), 1.45; C(2)–C(1), 1.54; C(2)–C(12), 1.53; C(6)–C(4), 1.499; C(4)–N(3)–C(2), 108.2; O(1)–N(1

Efficient catalytic alkyne metathesis with a fluoroalkoxy-supported ditungsten(III) complex

• Henrike Ehrhorn,
• Janin Schlösser,
• Dirk Bockfeld and
• Matthias Tamm

Beilstein J. Org. Chem. 2018, 14, 2425–2434, doi:10.3762/bjoc.14.220

• molecular structure of this complex was established by X-ray diffraction analysis. The ORTEP diagram is shown in Figure 2, and selected bond lengths and angles are displayed in Table 1. The tungsten–tungsten triple bond of 2.3452(2) Å falls in the range of previously reported bond lengths of this type [69

• applications of alkyne metathesis since this protocol represents a convenient approach to alkyne metathesis catalysts in two steps starting from WCl4. Selected homogeneous catalysts for alkyne metathesis. Molecular structure of W2F3·NHMe2 with thermal displacement parameters drawn at 50% probability. Hydrogen

• atoms are omitted for clarity. Molecular structure of WPhF3 with thermal displacement parameters drawn at 50% probability. Hydrogen atoms and minor components of the disordered OC(CF3)Me2 groups are omitted for clarity. Conversion versus time diagram for the self-metathesis of 1-phenyl-1-propyne

Determining the predominant tautomeric structure of iodine-based group-transfer reagents by ¹⁷O NMR spectroscopy

• Nico Santschi,
• Cody Ross Pitts,
• Benson J. Jelier and
• René Verel

Beilstein J. Org. Chem. 2018, 14, 2289–2294, doi:10.3762/bjoc.14.203

• represent 4c in solution. Does the compound resemble the molecular structure obtained in the solid state with oxygen still coordinated to iodine or would a free alcohol be a more accurate representation? In order to generate 4c, reagent 4a was treated with five equivalents of trifluoroacetic acid (TFA) and

Novel photochemical reactions of carbocyclic diazodiketones without elimination of nitrogen – a suitable way to N-hydrazonation of C–H-bonds

• Liudmila L. Rodina,
• Xenia V. Azarova,
• Jury J. Medvedev,
• Dmitrij V. Semenok and
• Valerij A. Nikolaev

Beilstein J. Org. Chem. 2018, 14, 2250–2258, doi:10.3762/bjoc.14.200

• (Supporting Information File 1, Figure S1). As it is evident from these data, the tricyclic diazodiketones 1b–e all have endo-configuration of the molecular structure. Analysis of the UV spectra of diazodiketones 1 shows that they have four absorption bands: two intense ones at 216–222 and 248–250 nm, and two

• tetrahydrofuran used in the project. Molecular structure of hydrazone 2b as determined by X-ray analysis data (Olex2 plot with 50% probability level of ellipsoids). Photochemical cycloelimination of furans from hydrazones 2d,e. Different pathways of diazodiketones 1 light-induced reactions in the singlet

Tetrathiafulvalene – a redox-switchable building block to control motion in mechanically interlocked molecules

• Hendrik V. Schröder and
• Christoph A. Schalley

Beilstein J. Org. Chem. 2018, 14, 2163–2185, doi:10.3762/bjoc.14.190

• states of 19. Schematic representation of a molecular electronic memory based on a bistable TTF-based rotaxane. (a) Molecular structure of the amphiphilic [2]rotaxane 20. (b) Structure of the crossbar device. (c) Switching mechanism of rotaxane 20 in a junction. Schematic representation of bending motion

Synthesis of 1,4-imino-L-lyxitols modified at C-5 and their evaluation as inhibitors of GH38 α-mannosidases

• Maroš Bella,
• Sergej Šesták,
• Ján Moncoľ,
• Miroslav Koóš and
• Monika Poláková

Beilstein J. Org. Chem. 2018, 14, 2156–2162, doi:10.3762/bjoc.14.189

• , further improvement of their potency against the target enzyme is needed. This could be achieved by introducing of different interacting group(s) at the aromatic unit that would ensure stronger interaction with the target enzyme. Structures of GMIIb inhibitors. Molecular structure (OLEX2 drawing with

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

• . bDMP (0.15 mmol) was used instead of PhI(OAc)2, reaction time 30 min. Molecular structure of 3ca. Atoms are presented as anisotropic displacement parameters (ADP) ellipsoids (50% probability). For clarity, only one set of positions of the disordered ethylene bridge and Ph groups is shown. CV curves of

Evaluation of dispersion type metal···π arene interaction in arylbismuth compounds – an experimental and theoretical study

• Ana-Maria Preda,
• Małgorzata Krasowska,
• Lydia Wrobel,
• Philipp Kitschke,
• Phil C. Andrews,
• Jonathan G. MacLellan,
• Lutz Mertens,
• Marcus Korb,
• Tobias Rüffer,
• Heinrich Lang,
• Alexander A. Auer and
• Michael Mehring

Beilstein J. Org. Chem. 2018, 14, 2125–2145, doi:10.3762/bjoc.14.187

• by diffusion of n-hexane into CH2Cl2 solution [53], but only gave a very brief description of the molecular structure. The Ar3Bi compound (C6H3-t-Bu2-3,5)3Bi (4) was prepared with a yield of 73% following the Grignard route, with the intention to study the influence of very bulky substituents

• is given here. A closer look at the bismuth environment reveals that for the molecular structure of 3 the bismuth atom might be described as six-coordinated being surrounded by six 4-methoxyphenyl groups. Three of them are bonded covalently to bismuth with Bi–C of 2.248(3) Å and three units are

D-Fructose-based spiro-fused PHOX ligands: synthesis and application in enantioselective allylic alkylation

• Michael R. Imrich,
• Jochen Kraft,
• Cäcilia Maichle-Mössmer and
• Thomas Ziegler

Beilstein J. Org. Chem. 2018, 14, 2082–2089, doi:10.3762/bjoc.14.182

• molecular structure is shown in Figure 2, detailed crystal data and structure refinements of the X-ray analysis are given in Supporting Information File 1. The configuration at the anomeric center is β and the fructose ring adopts 5C2 conformation. To confirm that the configuration of the major product of

• ligands 2 and 3 and spiro-fused PyOx and PHOX ligands 4 and 5. Molecular structure of 10j. Ellipsoids are given at the 50% probability level. Grey = carbon, red = oxygen, white = hydrogen, purple = nitrogen, orange = bromine. Preparation of 1,2-isopropylidene-protected D-fructose derivatives with

Chiral bisoxazoline ligands designed to stabilize bimetallic complexes

• Deepankar Das,
• Rudrajit Mal,
• Nisha Mittal,
• Zhengbo Zhu,
• Thomas J. Emge and
• Daniel Seidel

Beilstein J. Org. Chem. 2018, 14, 2002–2011, doi:10.3762/bjoc.14.175

• deprotonation, 32-H2 provides a dianionic ligand with three donor nitrogen atoms per metal center. Ligand 32-H2 forms complexes with different nickel, copper, zinc and palladium salts. Shown in Figure 6 is the molecular structure of 32·Zn2Cl2. Each unit of the complex 32·Zn2Cl2 consists of two zinc(ΙΙ) centers

• the development of new catalytic enantioselective transformations. Examples of chiral bimetallic complexes utilized in asymmetric catalysis. Previously reported bisoxazoline ligands capable of stabilizing bimetallic complexes. Thermal ellipsoid plot (50% probability) of the molecular structure of 16

• with a = 14.1829(5) Å, b = 14.8645(6) Å, c = 25.2342(10) Å, α = 90°, β = 90°, γ = 90°, V = 5319.9(4) Å3, Z = 4, Dc = 1.450 mg m−3 and μ(Mo Kα) = 1.017 mm−1. Thermal ellipsoid plot (50% probability) of the molecular structure of 25·Ni2(OAc). Hydrogen and solvate atoms have been omitted for clarity: (A

Synthesis of new p-tert-butylcalix[4]arene-based polyammonium triazolyl amphiphiles and their binding with nucleoside phosphates

• Vladimir A. Burilov,
• Guzaliya A. Fatikhova,
• Mariya N. Dokuchaeva,
• Ramil I. Nugmanov,
• Diana A. Mironova,
• Pavel V. Dorovatovskii,
• Victor N. Khrustalev,
• Svetlana E. Solovieva and
• Igor S. Antipin

Beilstein J. Org. Chem. 2018, 14, 1980–1993, doi:10.3762/bjoc.14.173

• [63] was used. Then optimized structures were calculated using DFT calculations with CPCM model of solvation in water with Gaussian 09 program [47] with B3LYP functional on 6-311g basis level. Molecular structure of 8a (50% ellipsoids). The dashed line indicates the alternative position of the

A hemicryptophane with a triple-stranded helical structure

• Augustin Long,
• Olivier Perraud,
• Erwann Jeanneau,
• Christophe Aronica,
• Jean-Pierre Dutasta and
• Alexandre Martinez

Beilstein J. Org. Chem. 2018, 14, 1885–1889, doi:10.3762/bjoc.14.162

• / UCBL, Université Claude Bernard Lyon 1, 6 rue victor Grignard, 69622 Villeurbanne cedex, France 10.3762/bjoc.14.162 Abstract A hemicryptophane cage bearing amine and amide functions in its three linkers was synthesized in five steps. The X-ray molecular structure of the cage shows a triple-stranded

• (400 MHz, CDCl3). X-ray molecular structure of 1. Hydrogen atoms are omitted for clarity; dashed lines represent hydrogen bonds. (a) Structure of compound 6. (b) 1H NMR of 6 (CDCl3, 400 MHz). (c) 1H NMR of 1 (CDCl3, 400 MHz). Synthesis of 1. Supporting Information Supporting Information File 396

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

• -donating substituents, in the coupling reaction. Examples of reported SCS palladium(II) pincer complexes 1–13. a) Reported SNS palladium(II) pincer complexes 14–16 as catalysts for Suzuki–Miyaura cross coupling [34]; b) Proposed SNS palladium(II) pincer complexes 17. Molecular structure of 17d. Selected

First thia-Diels–Alder reactions of thiochalcones with 1,4-quinones

• Grzegorz Mlostoń,
• Katarzyna Urbaniak,
• Paweł Urbaniak,
• Anna Marko,
• Anthony Linden and
• Heinz Heimgartner

Beilstein J. Org. Chem. 2018, 14, 1834–1839, doi:10.3762/bjoc.14.156

• (for C26H20O2S): 395 (100, [M − 1]−). ORTEP plot [29] of the molecular structure of 4k showing the major conformation of the disordered thiophene ring (50% probability ellipsoids; arbitrary numbering of the atoms). Products of the reactions of thiochalcones 1a and 1b with 1,4-benzoquinone (2a) and of

Recent advances in phosphorescent platinum complexes for organic light-emitting diodes

• Cristina Cebrián and
• Matteo Mauro

Beilstein J. Org. Chem. 2018, 14, 1459–1481, doi:10.3762/bjoc.14.124

• OLEDs. In fact, Wang and collaborators reported a red-emitting device based on Pt(fppz)2 [39], where fppz is 3-(trifluoromethyl)-5-(2-pyridyl)-1H-pyrazolate, that attained remarkable EQE of 31% [40] (see Figure 7 for the chemical structure of the complex). With the aim of correlating molecular structure

A three-armed cryptand with triazine and pyridine units: synthesis, structure and complexation with polycyclic aromatic compounds

• Claudia Lar,
• Adrian Woiczechowski-Pop,
• Attila Bende,
• Ioana Georgeta Grosu,
• Natalia Miklášová,
• Elena Bogdan,
• Niculina Daniela Hădade,
• Anamaria Terec and
• Ion Grosu

Beilstein J. Org. Chem. 2018, 14, 1370–1377, doi:10.3762/bjoc.14.115

• 21.34 M−1 ± 2.7909, respectively (M−1 = L/mol). The details of these experiments are given in Supporting Information File 1. The first step in the molecular modelling investigations was the optimization of the equilibrium geometry of the molecular structure of cryptand 2, the result being shown in

One hundred years of benzotropone chemistry

• Arif Dastan,
• Haydar Kilic and
• Nurullah Saracoglu

Beilstein J. Org. Chem. 2018, 14, 1120–1180, doi:10.3762/bjoc.14.98

• molecular structure of 4,5-benzotropone (11) was determined by Hata’s group [50]. X-ray diffraction analysis showed that the molecule is approximately planar and the bond alternation in the seven-membered ring and C=O bond length support satisfactory aromaticity. 2.1. Synthesis of 4,5-benzotropone (11

Fluorocyclisation via I(I)/I(III) catalysis: a concise route to fluorinated oxazolines

• Felix Scheidt,
• Christian Thiehoff,
• Gülay Yilmaz,
• Stephanie Meyer,
• Constantin G. Daniliuc,
• Gerald Kehr and
• Ryan Gilmour

Beilstein J. Org. Chem. 2018, 14, 1021–1027, doi:10.3762/bjoc.14.88

• the structure of oxazoline 2c bearing a p-NO2 group (Figure 4 and Table 2) [39]. The molecular structure reveals the expected gauche arrangement with a dihedral angle FCCO ≈ −73.4° due to σC–C→σC–F* and σC–H→σC–O* interactions. This observation is in agreement with the fluorine gauche effect

• increased to 32 hours. Yields refer to isolated values whilst NMR yields are given in parentheses (19F NMR using ethyl fluoroacetate as an internal standard). X-ray molecular structure of compound 2c. Thermal ellipsoids shown at the 50% propability level. Torsion angle (F1–C10–C9–O1 −73.4°) consistent with