Synthesis of organic liquid crystals containing selectively fluorinated cyclopropanes

• Zeguo Fang,
• Nawaf Al-Maharik,
• Peer Kirsch,
• Matthias Bremer,
• Alexandra M. Z. Slawin and
• David O’Hagan

Beilstein J. Org. Chem. 2020, 16, 674–680, doi:10.3762/bjoc.16.65

• University, Nablus, Palestine Merck KGaA, Liquid Crystal R&D Chemistry, Frankfurter Str. 250, 64293 Darmstadt, Germany 10.3762/bjoc.16.65 Abstract This paper describes the synthesis of a series of organic liquid crystals (LCs) containing selectively fluorinated cyclopropanes at their termini. The syntheses

• negative dielectric anisotropy. The study gives some guidance into effective structure–property relationships for the design of LCs containing selectively fluorinated cyclopropane motifs. Keywords: dielectric anisotropy; difluorocarbene; organic liquid crystals; selectively fluorinated cyclopropanes

• the requirements for different LCD technologies. For the traditional twisted nematic (TN) LCD technology, devices require liquid crystals with display positive dielectric anisotropy by which the molecular dipole moment is oriented parallel to the long axis of the molecule, while for the current

Direct borylation of terrylene and quaterrylene

• Haruka Kano,
• Keiji Uehara,
• Kyohei Matsuo,
• Hironobu Hayashi,
• Hiroko Yamada and
• Naoki Aratani

Beilstein J. Org. Chem. 2020, 16, 621–627, doi:10.3762/bjoc.16.58

• singlet peaks at 8.58, 8.37 and 8.23 ppm due to aromatic protons. The structure of TB4 was unambiguously revealed by single crystal X-ray diffraction analysis (Figure 2). The crystals suitable for X-ray diffraction were obtained by vapor diffusion of hexane into a solution of TB4 in CH2Cl2. The terrylene

• crystals, resulting in the 1D columnar structure as a whole, which is expected to have higher carrier mobility. Recently, oligo-perinaphthalenes, namely oligorylenes, are of great interest as good model compounds of armchair graphene nanoribbons (AGNRs), since AGNRs with a width of N = 3p + 2 are predicted

Six-fold C–H borylation of hexa-peri-hexabenzocoronene

• Mai Nagase,
• Kenta Kato,
• Akiko Yagi,
• Yasutomo Segawa and
• Kenichiro Itami

Beilstein J. Org. Chem. 2020, 16, 391–397, doi:10.3762/bjoc.16.37

• subjected to X-ray crystallographic analysis. Orange single crystals were formed by the diffusion of pentane vapor to a 1,1,1-trichloroethane solution of 1 synthesized by the C–H borylation method. The crystal structure confirmed that the C–H borylation proceeded regioselectively at the least hindered C–H

Synthesis and circularly polarized luminescence properties of BINOL-derived bisbenzofuro[2,3-b:3’,2’-e]pyridines (BBZFPys)

• Ryo Takishima,
• Yuji Nishii,
• Tomoaki Hinoue,
• Yoshitane Imai and
• Masahiro Miura

Beilstein J. Org. Chem. 2020, 16, 325–336, doi:10.3762/bjoc.16.32

• numerous attempts for obtaining crystals suitable for the X-ray analysis. Based on these observations, it is reasonable to conclude that the tert-butyl substituents effectively restricted the stacking structure to the specific conformations, thereby facilitating the assembly of well-ordered aggregates in

• -state structures were investigated by X-ray diffraction analysis to find well-ordered intermolecular stacking structures within the crystals. Experimental General All manipulations were performed under N2 using standard Schlenk techniques unless otherwise noted. DMF was dried and deoxygenated by a Glass

• . Compound 4b: Synthesized similarly to 4b from 3b (254 mg, 0.30 mmol). Purified by silica gel column chromatography (eluent: hexane/EtOAc 4:1) and GPC to give the title compound as pale yellow solid; (S)-4b (45.4 mg, 18% yield), (R)-4b (30.2 mg, 12% yield). Single crystals suitable for the X-ray analysis

Absolute configurations of talaromycones A and B, α-diversonolic ester, and aspergillusone B from endophytic Talaromyces sp. ECN211

• Ken-ichi Nakashima,
• Junko Tomida,
• Takao Hirai,
• Yoshiaki Kawamura and
• Makoto Inoue

Beilstein J. Org. Chem. 2020, 16, 290–296, doi:10.3762/bjoc.16.28

• in good agreement with those of 1 (Figure 3b), the absolute configuration of 2 was also assigned to be R. Single crystals of α-diversonolic ester (3) were obtained as colorless prisms by vapor diffusion with acetone/n-hexane, and single-crystal X-ray diffractometry determined the structure shown in

•  4b). This is the first experimental evidence that corroborates the absolute configurations of 3 and 4, compounds that were reported previously without evidence for this stereochemistry. We also obtained single crystals of glauconic acid (5) as prisms by slow evaporation in CH2Cl2/n-hexane at 10 °C. X

• :1, v/v) as eluent. The fractions were pooled according to TLC analysis to yield nine combined fractions (F1–9). F2 was subjected to ODS column chromatography with MeCN/H2O (stepwise gradient, 3:7, 2:3, and 1:1, v/v) to yield 1 (45.3 mg). F4 was recrystallized from CH2Cl2 to obtain crude crystals of

Ultrasonic-assisted unusual four-component synthesis of 7-azolylamino-4,5,6,7-tetrahydroazolo[1,5-a]pyrimidines

• Yana I. Sakhno,
• Maryna V. Murlykina,
• Oleksandr I. Zbruyev,
• Anton V. Kozyryev,
• Svetlana V. Shishkina,
• Dmytro Sysoiev,
• Vladimir I. Musatov,
• Sergey M. Desenko and
• Valentyn A. Chebanov

Beilstein J. Org. Chem. 2020, 16, 281–289, doi:10.3762/bjoc.16.27

• Yana I. Sakhno Maryna V. Murlykina Oleksandr I. Zbruyev Anton V. Kozyryev Svetlana V. Shishkina Dmytro Sysoiev Vladimir I. Musatov Sergey M. Desenko Valentyn A. Chebanov Division of Chemistry of Functional Materials, State Scientific Institution “Institute for Single Crystals” of National Academy

Synthesis and herbicidal activities of aryloxyacetic acid derivatives as HPPD inhibitors

• Man-Man Wang,
• Hao Huang,
• Lei Shu,
• Jian-Min Liu,
• Jian-Qiu Zhang,
• Yi-Le Yan and
• Da-Yong Zhang

Beilstein J. Org. Chem. 2020, 16, 233–247, doi:10.3762/bjoc.16.25

• Supporting Information File 1. The chemical structures of all title compounds were confirmed by 1H and 13C NMR spectroscopic analyses and HRMS spectrometric analyses. X-ray diffraction Single crystals of compounds I18 and III4 were cultivated for structure validation. Compound I18 was recrystallized from a

Synthesis of 4-(2-fluorophenyl)-7-methoxycoumarin: experimental and computational evidence for intramolecular and intermolecular C–F···H–C bonds

• Vuyisa Mzozoyana,
• Fanie R. van Heerden and
• Craig Grimmer

Beilstein J. Org. Chem. 2020, 16, 190–199, doi:10.3762/bjoc.16.22

• has not been reported previously [CCDC No.: 1868146]. The crystals of 6 were obtained by slow evaporation of methanol/dichloromethane and were found to be of the monoclinic crystal system with space group C2/c (Figure 7). The crystal structure shows that the fluorinated phenyl ring is at a torsion

The use of isoxazoline and isoxazole scaffolding in the design of novel thiourea and amide liquid-crystalline compounds

• Itamar L. Gonçalves,
• Rafaela R. da Rosa,
• Vera L. Eifler-Lima and
• Aloir A. Merlo

Beilstein J. Org. Chem. 2020, 16, 175–184, doi:10.3762/bjoc.16.20

• Ciências e Tecnologia, Universidade NOVA de Lisboa, 2829-516 Caparica, Portugal Institute of Chemistry, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil 10.3762/bjoc.16.20 Abstract A series of novel thiourea and amide liquid crystals containing 5-membered isoxazoline and isoxazole rings

• crystals containing hydrogen bonds may exhibit a wide variety of phase polymorphism depending on the length of the chain, type of bonding and the functional groups involved [12][28][29][30]. Many liquid crystalline compounds have been developed exploring the ability of hydrogen bonding formation between

Synthesis, liquid crystalline behaviour and structure–property relationships of 1,3-bis(5-substituted-1,3,4-oxadiazol-2-yl)benzenes

• Afef Mabrouki,
• Malek Fouzai,
• Armand Soldera,
• Abdelkader Kriaa and
• Ahmed Hedhli

Beilstein J. Org. Chem. 2020, 16, 149–158, doi:10.3762/bjoc.16.17

• moments were also investigated. Keywords: dipole moment; fluorine; liquid crystal; oxadiazole; Introduction Liquid-crystalline (LC) materials have been known for over a century [1]. It is clear that architecture and functionalization are essential aspects in molecular engineering of liquid crystals [2

• the fluorine atom leads to a subtle modification of properties such as melting point, mesophase morphology, transition temperatures, optical anisotropy, dielectric anisotropy, and visco-elasticity [5][6][7][8][9][10]. Therefore, many fluorinated liquid crystals have been prepared, and the fluoro

• -substitution effect has been well studied, especially in the fluoroaromatic derivatives [11][12][13]. Additionally, the mesomorphic properties of liquid crystals depend strongly on the nature of the terminal chains that are present. A terminal perfluorocarbon chain present in a LC molecule causes stiffening

Synthesis of 3-alkenylindoles through regioselective C–H alkenylation of indoles by a ruthenium nanocatalyst

• Abhijit Paul,
• Debnath Chatterjee,
• Srirupa Banerjee and
• Somnath Yadav

Beilstein J. Org. Chem. 2020, 16, 140–148, doi:10.3762/bjoc.16.16

• essentially zerovalent Ru nanoparticles promotes their catalytic ability towards several challenging reactions, such as CO oxidation [67][68] and hydrogen evolution [69]. Interestingly, pristine Ru(0) single crystals have been reported to perform poorly in these reactions when compared to the surface-oxidised

Reversible photoswitching of the DNA-binding properties of styrylquinolizinium derivatives through photochromic [2 + 2] cycloaddition and cycloreversion

• Sarah Kölsch,
• Heiko Ihmels,
• Jochen Mattay,
• Norbert Sewald and
• Brian O. Patrick

Beilstein J. Org. Chem. 2020, 16, 111–124, doi:10.3762/bjoc.16.13

• single crystals after slow evaporation, their structure was determined by single crystal X-ray diffraction (XRD) analysis (Figure 8, cf. Supporting Information File 1). The cyclobutane 4b crystallized from water in the monoclinic space group P21/n, and the derivative 4c crystallized from water in the

[1,3]/[1,4]-Sulfur atom migration in β-hydroxyalkylphosphine sulfides

• Katarzyna Włodarczyk,
• Piotr Borowski and
• Marek Stankevič

Beilstein J. Org. Chem. 2020, 16, 88–105, doi:10.3762/bjoc.16.11

• compounds failed to give single crystals for X-ray analysis. The presence of an oxygen atom attached to the phosphorus atom in the products could be deduced based on 1H and 13C NMR analysis. In the 1H NMR spectra of phosphine sulfide 12, the chemical shifts of the signals belonging to the aromatic protons

Halogen-bonding-induced diverse aggregation of 4,5-diiodo-1,2,3-triazolium salts with different anions

• Xingyu Xu,
• Shiqing Huang,
• Zengyu Zhang,
• Lei Cao and
• Xiaoyu Yan

Beilstein J. Org. Chem. 2020, 16, 78–87, doi:10.3762/bjoc.16.10

• evaporation of dichloromethane solution. The treatment of 2-I with 2 equivalents iodine or 4 equivalents iodine afforded triazolium polyiodide 2-I.1.5I2 and 2-I.3.5I2, respectively. The single crystals were obtained by slow diffusion of ether into a dichloromethane solution. The crystal X-ray analyses of 2-I

• the former shows a boat conformation and the latter forms a rectangle conformation. Triazolium salts form a linear polymer with polyiodide. 2-BF4 forms co-crystals with 4,4'-bipyridine via halogen bonding. DFT calculation results show that the σ holes of 4,5-diiodo-1,2,3-triazolium is similar to the σ

• ), 110.0, 21.4, 17.4; anal. calcd. for C22H22F3I2N3O2 (671.24): C, 39.37, H, 3.30, N, 6.26%; found: C, 39.51, H, 3.49, N, 6.18%. 2-I.1.5I2: 2-I (35 mg, 0.05 mol) and I2 (25 mg, 0.1 mmol) were mixed in dichloromethane (6 mL) in a round bottom flask. The single crystals were obtained by slow diffusion of

Influence of the cis/trans configuration on the supramolecular aggregation of aryltriazoles

• Sara Tejera,
• Giada Caniglia,
• Rosa L. Dorta,
• Andrea Favero,
• Javier González-Platas and
• Jesús T. Vázquez

Beilstein J. Org. Chem. 2019, 15, 2881–2888, doi:10.3762/bjoc.15.282

• 12 led to single crystals suitable for X-ray crystallography. Its analysis (Figure 3) not only confirmed the structure, but in addition showed a well-organized crystal packing (Figure 4) where the alternate disposition of the molecules displayed a parallelism between the p-bromophenyl groups as well

• as between the triazole rings, and therefore the presence of multiple intermolecular π–π stacking and π–bromine [19] interactions. This compound precipitated in the presence of any amount of water and gelled only in DMSO at a low temperature. Compound 10 produced pseudo-crystals in DMSO/H2O (1:1, v/v

Design, synthesis and investigation of water-soluble hemi-indigo photoswitches for bioapplications

• Daria V. Berdnikova

Beilstein J. Org. Chem. 2019, 15, 2822–2829, doi:10.3762/bjoc.15.275

• ), 136.0 (1C, C-4), 153.9 (1C, C-2), 159.6 (1C, C-14), 186.0 (1C, C-8) ppm); Anal. calcd for C16H13NO2: C, 76.48; H, 5.21; N, 5.57; found: C, 76.31 H, 5.15; N, 5.50 %; ESIMS (MeOH, m/z): 250 [Z-1b − H]−. (Z)-2-(3,4-Dimethoxybenzylidene)indolin-3-one (Z-1c) Orange crystals, yield 66% (211 mg, 0.75 mmol); mp

Diversity-oriented synthesis of spirothiazolidinediones and their biological evaluation

• Sambasivarao Kotha,
• Gaddamedi Sreevani,
• Lilya U. Dzhemileva,
• Milyausha M. Yunusbaeva,
• Usein M. Dzhemilev and
• Vladimir A. D’yakonov

Beilstein J. Org. Chem. 2019, 15, 2774–2781, doi:10.3762/bjoc.15.269

• , the formazan crystals were dissolved in 150 μL of DMSO, and the absorbance was determined at 595 nm using a microplate spectrophotometer. The IC50 value was determined from plots of percent viability against the dose of the compound added. Cytotoxicity assay: Viability (live/dead) assessment was

Synthesis of aryl-substituted thieno[3,2-b]thiophene derivatives and their use for N,S-heterotetracene construction

• Nadezhda S. Demina,
• Nikita A. Kazin,
• Nikolay A. Rasputin,
• Roman A. Irgashev and
• Gennady L. Rusinov

Beilstein J. Org. Chem. 2019, 15, 2678–2683, doi:10.3762/bjoc.15.261

• crystals of some of these compounds, however, all of them formed powdery precipitates. Therefore, N-functionalization of compound 6d was carried out with benzyl bromide in the presence of NaH (Scheme 4). The resulting benzyl derivative 7d was crystallized from ethyl acetate to give crystals, which were

Unexpected one-pot formation of the 1H-6a,8a-epiminotricyclopenta[a,c,e][8]annulene system from cyclopentanone, ammonia and dimethyl fumarate. Synthesis of highly strained polycyclic nitroxide and EPR study

• Sergey A. Dobrynin,
• Igor A. Kirilyuk,
• Yuri V. Gatilov,
• Andrey A. Kuzhelev,
• Olesya A. Krumkacheva,
• Matvey V. Fedin,
• Michael K. Bowman and
• Elena G. Bagryanskaya

Beilstein J. Org. Chem. 2019, 15, 2664–2670, doi:10.3762/bjoc.15.259

• 4:1). 1: 70 mg (5%); colorless crystals; mp 146.8–148.4 °C; IR (KBr): 3298 (N-H), 1734, 1718 (C=O); 1H NMR (400 MHz, CDCl3, δ) 1.08–1.16 (m, 1H), 1.35–1.48 (m, 3H), 1.49–1.57 (m, 1H), 1.60–1.69 (m, 3H), 1.70–1.76 (m, 1H), 1.84–1.90 (m,1H), 1.91–1.98 (m, 2H), 1.99–2.08 (m, 3H), 2.14–2.20 (m, 1H

• silica gel (hexane/ethyl acetate 4:1). 2: 56 mg (48%); red crystals; mp 127.0 °C dec, IR (KBr): 3438 (O-H) 1730 (C=O); X-ray: triclinic system, P-1, a = 8.2240(5), b = 10.9423(6), c = 11.4515(8) Å, α = 83.440(3), β = 75.611(3), γ = 83.119(2)º, V = 987.17(11) Å3, Z = 2, 2θmax = 27.292°, 4388 independent

Plasma membrane imaging with a fluorescent benzothiadiazole derivative

• Pedro H. P. R. Carvalho,
• Jose R. Correa,
• Karen L. R. Paiva,
• Daniel F. S. Machado,
• Jackson D. Scholten and
• Brenno A. D. Neto

Beilstein J. Org. Chem. 2019, 15, 2644–2654, doi:10.3762/bjoc.15.257

• incubated with 150 μL of MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) solution (0.5 mg mL−1) in cell culture medium for 4 h in the dark at 37 °C (MTT is reduced by metabolically active cells to insoluble purple formazan dye crystals that accumulate inside the cell cytoplasm

• ). Afterwards, the MTT solution is removed and 200 μL of DMSO are added to all samples to solubilize the formazan dye crystals. The plate was read in spectrophotometer and the optimal wavelength for absorbance was 570 nm. The MTT assay was performed in triplicate and also made three independent assays. The cell

Nanangenines: drimane sesquiterpenoids as the dominant metabolite cohort of a novel Australian fungus, Aspergillus nanangensis

• Heather J. Lacey,
• Cameron L. M. Gilchrist,
• Andrew Crombie,
• John A. Kalaitzis,
• Daniel Vuong,
• Peter J. Rutledge,
• Peter Turner,
• John I. Pitt,
• Ernest Lacey,
• Yit-Heng Chooi and
• Andrew M. Piggott

Beilstein J. Org. Chem. 2019, 15, 2631–2643, doi:10.3762/bjoc.15.256

• C22H35O5+ [M – H2O + H]+, 379.2479; found, 379.2473. Crystallography Crystals suitable for single crystal X-ray diffraction analysis were obtained for 1, 4 and 9, providing confirmation of the spectroscopic structural elucidation. Indirect confirmation of the structures of 2 and 3 was obtained following

• their conversion to 4-bromobenzoyl ester derivatives, with substitution at the C-9 and C-1 hydroxy groups respectively, and the growth of crystals of these derivatives (2b and 3b). The X-ray diffraction data obtained from single crystals of 4 and 9 did not allow a definitive determination of their

1,5-Phosphonium betaines from N-triflylpropiolamides, triphenylphosphane, and active methylene compounds

• Vito A. Fiore,
• Chiara Freisler and
• Gerhard Maas

Beilstein J. Org. Chem. 2019, 15, 2603–2611, doi:10.3762/bjoc.15.253

• usually colorless, while the Z-isomers have a yellow shade. As an exception, E-3f was obtained as dark red needle-shaped crystals, in contrast to pale yellow blocks of Z-3f. All betaines could be stored unchanged at least for a year under a dry atmosphere. They appear to be somewhat hygroscopic, as the

Synthetic terpenoids in the world of fragrances: Iso E Super^® is the showcase

• Alexey Stepanyuk and
• Andreas Kirschning

Beilstein J. Org. Chem. 2019, 15, 2590–2602, doi:10.3762/bjoc.15.252

• challenges to be solved. Hydrophilic and hydrophobic interactions with the unpolar lipid layer make the tendency to yield suitable crystals even more difficult. Nevertheless, Palczewski and co-workers were able to crystallise the first GPCR (G-protein-coupled receptor) in 2000 confirming the previously

Safe and highly efficient adaptation of potentially explosive azide chemistry involved in the synthesis of Tamiflu using continuous-flow technology

• Cloudius R. Sagandira and
• Paul Watts

Beilstein J. Org. Chem. 2019, 15, 2577–2589, doi:10.3762/bjoc.15.251

• concentrated in vacuo to afford pure compound 7 as white crystals. Solid: mp 136.9–138.2 °C (Lit. value [9] mp. 136.6–137.7 °C); FTIR (cm−1) ν: 3266, 2971, 2099, 1713, 1658, 1558, 1249, 1075; 1H NMR (400 MHz, CDCl3) δ 0.91 (m, 6H), 1.31 (t, J = 7.1 Hz, 3H), 1.42–1.63 (m, 4H), 2.10 (s, 3H), 2.18–2.33 (m, 1H

Formation of alkyne-bridged ferrocenophanes using ring-closing alkyne metathesis on 1,1’-diacetylenic ferrocenes

• Celine Bittner,
• Dirk Bockfeld and
• Matthias Tamm

Beilstein J. Org. Chem. 2019, 15, 2534–2543, doi:10.3762/bjoc.15.246

• solutions of 1a and 1b after layering with pentane or hexane, respectively, crystals suitable for X-ray diffraction analysis could be obtained. The corresponding ORTEP drawings are given in Figure 3 and Figure 4. Ferrocene 1a crystallises in the orthorhombic space group Pca21, while the analogues compound

• disorder on the iron position. Unfortunately, no single crystals for X-ray diffraction analysis could be obtained with such disorder being absent. For the catalytic RCAM (Scheme 1), the substrates 1a and 1b were dissolved in toluene at high dilution (4.5 mM), and the catalyst MoF6 (2 mol %) was added as a

• experimental section in Supporting Information File 1). Crystals of 2a suitable for X-ray diffraction analysis could be obtained from a hot saturated solution in toluene after cooling to −28 °C. An ORTEP drawing is given in Figure 5. The ferrocenophane 2a crystallises in the orthorhombic space group Pbcn with