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Search for "molecular electronics" in Full Text gives 33 result(s) in Beilstein Journal of Organic Chemistry.
Efficient synthesis of phenylene-ethynylene rods and their use as rigid spacers in divalent inhibitors
- Francesca Pertici,
- Norbert Varga,
- Arnoud van Duijn,
- Matias Rey-Carrizo,
- Anna Bernardi and
- Roland J. Pieters
Beilstein J. Org. Chem. 2013, 9, 215–222, doi:10.3762/bjoc.9.25
- units the phenylene-ethynylene unit has seen considerable interest in sensor [16] and molecular-electronics applications [17]. This is due to the specific fluorescent, conducting and electrochemical properties that the conjugated system confers to the molecule [18]. In the study of carbohydrate–protein
Graphical Abstract
Figure 1: Schematic depiction of (a) a rigid phenylene-ethynylene polymer core with ligands attached via flex...
Figure 2: Generic structure of spacers containing an even (n = 1, 3) and an odd (n = 2, 4) number of units.
Figure 3: Synthetic strategy for rigid spacers with an even number of units.
Figure 4: Synthetic strategy for rigid spacers with an odd number of units.
Scheme 1: Synthesis of building blocks; (a) from 1, Pd(PPh3)4 , CuI, PPh3, TEA, toluene, 50 °C, 5 h, 31% for 3...
Scheme 2: Synthesis of a two-unit spacer. (a) PdCl2(PPh3)2, CuI, TEA, THF, microwave, 60 °C, 20 min, 81% for 7...
Scheme 3: Synthesis of three-unit spacers. (a) from 4: TBAF, THF, 62%; from 6 and 14: K2CO3, MeOH/CH2Cl2, 45 ...
Scheme 4: Synthesis of a four-unit spacer. (a) PdCl2(PPh3)2, CuI, TEA, THF, microwave, 60 °C, 20 min, 73%; (b...
Scheme 5: Synthesis of a five-unit spacer. (a) PdCl2(PPh3)2, CuI, TEA, THF, microwave, 60 °C, 20 min, 70%; (b...
Scheme 6: Synthesis of divalent ligand 22. (a) CuSO4·5H2O, Na-ascorbate, DMF/H2O, microwave, 80 °C, 40 min, 8...
Scheme 7: Synthesis of divalent ligand 24. (a) 13, TBAF in THF, rt, 1 h, then H2O, TBTA, CuSO4·5H2O, Na-ascor...
Figure 5: Previously tested compounds.
The effect of the formyl group position upon asymmetric isomeric diarylethenes bearing a naphthalene moiety
- Renjie Wang,
- Shouzhi Pu,
- Gang Liu and
- Shiqiang Cui
Beilstein J. Org. Chem. 2012, 8, 1018–1026, doi:10.3762/bjoc.8.114
- ; Introduction In the past decade, photochromic materials have received much attention because of their applications in potential photoswitchable, molecular devices and optical memory storage systems [1]. Among these materials, the utilization of diarylethene derivatives in molecular electronics, optical memory
Graphical Abstract
Scheme 1: Photochromism of diarylethenes 1–3.
Scheme 2: Synthetic route for diarylethenes 1–3.
Figure 1: Absorption spectral changes of diarylethenes 1–3 by photoirradiation with UV–vis in hexane (2.0 × 10...
Figure 2: The color changes of diarylethene 1–3 by photoirradiation at room temperature: (A) in hexane; (B) i...
Figure 3: The photoconversion ratios of diarylethenes 1–3 in the photostationary state as analyzed by HPLC.
Figure 4: Fatigue resistance of diarylethenes 1–3 in hexane in air atmosphere at room temperature: (A) in hex...
Figure 5: Fluorescence emission spectra of diarylethenes 1–3 at room temperature: (A) in hexane solution (2.0...
Figure 6: Emission intensity changes of diarylethene 1 upon irradiation with UV light at room temperature: (A...
Figure 7: Cyclic voltammetry of diarylethenes 1–3 in acetonitrile with a scanning rate of 50 mV/s.
On the bromination of the dihydroazulene/vinylheptafulvene photo-/thermoswitch
- Virginia Mazzanti,
- Martina Cacciarini,
- Søren L. Broman,
- Christian R. Parker,
- Magnus Schau-Magnussen,
- Andrew D. Bond and
- Mogens B. Nielsen
Beilstein J. Org. Chem. 2012, 8, 958–966, doi:10.3762/bjoc.8.108
- , renders the system interesting as a light-controlled molecular switch in, for example, molecular electronics. Indeed, light-induced conductance switching was recently observed for a DHA derivative situated in a single-molecule junction [4]. For the further exploration of the DHA/VHF switch in this field
Graphical Abstract
Scheme 1: Dihydroazulene (DHA)/vinylheptafulvene (VHF) photo-/thermoswitch.
Figure 1: Numbering of azulene.
Scheme 2: Bromination–elimination protocol for functionalization of DHA [3,5-8]. HMDS = hexamethyldisilazide.
Scheme 3: Bromination of VHF [11]. NBS = N-bromosuccinimide.
Scheme 4: Radical and ionic brominations of VHF.
Figure 2: 1H,1H COSY NMR spectrum of DHA 8 (CDCl3, 500 MHz). For assignments of DHA signals, see numbering in ...
Figure 3: Molecular structures (with displacements ellipsoids at 50% probability for non-H atoms) of (a) DHA 8...
Figure 4: 1H NMR spectra (C6D6, 300 MHz) of (a) DHA 1; (b) VHF 2; (c–e) VHF 2 after treatment with 2 molar eq...
Figure 5: Compound 9 was selectively brominated to furnish the product 10.
Scheme 5: Synthesis of 3,7-dibromo-DHA.
Scheme 6: Synthesis of a 3,7-dibromoazulene.
Scheme 7: Regioselective Sonogashira and Suzuki couplings. RuPhos = 2-dicyclohexylphosphino-2',6'-diisopropox...
Scheme 8: Slow conversions to azulenes in the solid state.
Figure 6: Absorption spectra of DHA 8 and VHF 7 in cyclohexane. The broken curve shows the absorption spectru...
Liquid-crystalline nanoparticles: Hybrid design and mesophase structures
- Gareth L. Nealon,
- Romain Greget,
- Cristina Dominguez,
- Zsuzsanna T. Nagy,
- Daniel Guillon,
- Jean-Louis Gallani and
- Bertrand Donnio
Beilstein J. Org. Chem. 2012, 8, 349–370, doi:10.3762/bjoc.8.39
- growth. These properties have led to their exploitation in a number of applications, from catalysis and molecular electronics to nanomedicine [77], and their use in liquid crystal applications is relatively well established [31][78]. Recognising this potential, a study was reported [79] in which a series
Graphical Abstract
Figure 1: Three of the common molecular and supramolecular structural motifs in liquid crystal chemistry: rod...
Figure 2: Schematic representation of the solvent-mediated ligand exchange process, illustrated for the parti...
Figure 3: Chemical structures and LC properties of the rodlike ligands discussed in the text.
Figure 4: Schematic representation of pseudospherical Au NPs coated exclusively with mesogenic rodlike ligand...
Figure 5: TEM images of Au@612 (a) before and (b) after thermal treatment. Below: Proposed model of the nanop...
Figure 6: Ligand deformation at the surface of the gold NPs giving rigid "poles" and a soft equator. Such def...
Figure 7: A simplified illustration of the local rectangular arrangement of nanoparticles in a condensed mixe...
Figure 8: Chemical structures and LC properties of the rodlike ligands discussed in the text.
Figure 9: Schematic drawing of the arrangement of nanoparticles in the columnar phase, as viewed from above (...
Figure 10: The proposed structural models resulting from ligand migration at the NP surface: (a) Smectic (Au@C6...
Figure 11: Reversible migration of the surface ligands as a function of temperature (and phase). Only the blue...
Figure 12: Photochromic and photo-mesogenic rodlike ligands.
Figure 13: Chemical structures and LC properties of side-on mesogens used to coat NPs.
Figure 14: Left: POM image of ligand 12. Right: POM image of Schlieren texture of the hybrid Au@12. Reprinted ...
Figure 15: Threaded nematic texture of Au@ C12/13 as observed by POM at RT. Scale bar = 10 μm. Reprinted with ...
Figure 16: Schematic representation of the gold NP columnar structures. (a) Rhombohedral phase in Au@C12/13 an...
Figure 17:
TEM images of thin films of the ![[Graphic 5]](/bjoc/content/inline/1860-5397-8-39-i5.png?max-width=637&scale=1.18182)
phase of Au@C12/13 recorded with the beam (a) parallel to the ![[Graphic 6]](/bjoc/content/inline/1860-5397-8-39-i6.png?max-width=637&scale=1.18182)
pla...
Figure 18: Chemical structures and mesogenic properties of bent-core proto-mesogenic ligands used to coat NPs.
Figure 19: Chemical structures and mesogenic properties of dendritic and proto-dendritic ligands used to coat ...
Figure 20: TEM image showing the arrangement of the hybrid NPs Au@16 into regularly spaced rows. Reprinted wit...
Figure 21: Chemical structures and mesogenic properties of dendritic and proto-dendritic ligands used to coat ...
Figure 22:
Top left: Body-centred (I) cubic lattice of ![[Graphic 8]](/bjoc/content/inline/1860-5397-8-39-i8.png?max-width=637&scale=1.18182)
symmetry composed of truncated octahedrons. Top right:...
Figure 23: Model proposed for the organisation of the hybrids within the quasi-nematic mesophase. Reprinted wi...
Figure 24: Mesogenic dendrons used to coat Au NPs.
Figure 25: Chemical structures of the discotic mesogenic ligands used to coat NPs.
Figure 26: TEM images of Au@235,12 prepared from aged solutions stood for 10 days in solutions of (a) 1:1 MeOH...
Figure 27: Some of the various hybrid geometries and packing motifs possible upon ligand grafting to the surfa...
Synthesis, electronic properties and self-assembly on Au{111} of thiolated (oligo)phenothiazines
- Adam W. Franz,
- Svetlana Stoycheva,
- Michael Himmelhaus and
- Thomas J. J. Müller
Beilstein J. Org. Chem. 2010, 6, No. 72, doi:10.3762/bjoc.6.72
- become a groundbreaking strategy in the development of molecular electronics [6]. In recent years, many investigations into SAMs of organic molecules on gold surfaces have been carried out [7]. Thiols, thiol esters, and disulfides can be easily chemisorbed on gold to form SAMs by exposure of well-defined
Graphical Abstract
Scheme 1: Synthesis of (oligo)phenothiazinyl thioacetates 2 and 4.
Figure 1: Normalized absorption (solid line) and emission (dashed line) spectra of thioacetate 2d (recorded i...
Figure 2: Cyclic voltammogram of thioacetate 2d (recorded in CH2Cl2, T = 293 K; 0.1 M electrolyte [Bu4N][PF6]...
Scheme 2: Preparation of SAMs from (oligo)phenothiazinyl thioacetates 2 or 4 on a Au{111}-coated silicon wafe...
Molecular recognition of organic ammonium ions in solution using synthetic receptors
- Andreas Späth and
- Burkhard König
Beilstein J. Org. Chem. 2010, 6, No. 32, doi:10.3762/bjoc.6.32
Graphical Abstract
Figure 1: Biologically important amines and quaternary ammonium salts: histamine (1), dopamine (2) and acetyl...
Figure 2: Crown ether 18-crown-6.
Figure 3: Conformations of 18-crown-6 (4) in solvents of different polarity.
Figure 4: Binding topologies of the ammonium ion depending on the crown ring size.
Figure 5: A “pseudorotaxane” structure consisting of 24-crown-8 and a secondary ammonium ion (5); R = Ph.
Figure 6: Typical examples of azacrown ethers, cryptands and related aza macrocycles.
Figure 7: Binding of ammonium to azacrown ethers and cryptands [111-113].
Figure 8: A 19-crown-6-ether with decalino blocking groups (11) and a thiazole-dibenzo-18-crown-6-ether (12).
Figure 9: 1,3-Bis(6-oxopyridazin-1-yl)propane derivatives 13 and 14 by Campayo et al.
Figure 10: Fluorescent azacrown-PET-sensors based on coumarin.
Figure 11: Two different pyridino-cryptands (17 and 18) compared to a pyridino-crown (19); chiral ammonium ion...
Figure 12: Pyridino-18-crown-6 ligand (21), a similar acridino-18-crown-6 ligand (22) and a structurally relat...
Figure 13: Ciral pyridine-azacrown ether receptors 24.
Figure 14: Chiral 15-crown-5 receptors 26 and an analogue 18-crown-6 ligand 27 derived from amino alcohols.
Figure 15: C2-symmetric chiral 18-crown-6 amino alcohol derivatives 28 and related macrocycles.
Figure 16: Macrocycles with diamide-diester groups (30).
Figure 17: C2-symmetric chiral aza-18-crown-6 ethers (31) with phenethylamine residues.
Figure 18: Chiral C-pivot p-methoxy-phenoxy-lariat ethers.
Figure 19: Chiral lariat crown ether 34.
Figure 20: Sucrose-based chiral crown ether receptors 36.
Figure 21: Permethylated fructooligosaccharide 37 showing induced-fit chiral recognition.
Figure 22: Biphenanthryl-18-crown-6 derivative 38.
Figure 23: Chiral lariat crown ethers derived from binol by Fuji et al.
Figure 24: Chiral phenolic crown ether 41 with “aryl chiral barriers” and guest amines.
Figure 25: Chiral bis-crown receptor 43 with a meso-ternaphthalene backbone.
Figure 26: Chromogenic pH-dependent bis-crown chemosensor 44 for diamines.
Figure 27: Triamine guests for binding to receptor 44.
Figure 28: Chiral bis-crown phenolphthalein chemosensors 46.
Figure 29: Crown ether amino acid 47.
Figure 30: Luminescent receptor 48 for bis-alkylammonium guests.
Figure 31: Luminescent CEAA (49a), a bis-CEAA receptor for amino acids (49b) and the structure of lysine bindi...
Figure 32: Luminescent CEAA tripeptide for binding small peptides.
Figure 33: Bis crown ether 51a self assembles co-operatively with C60-ammonium ion 51b.
Figure 34: Triptycene-based macrotricyclic dibenzo-[24]-crown-8 ether host 52 and guests.
Figure 35: Copper imido diacetic acid azacrown receptor 53a and the suggested His-Lys binding motif; a copper ...
Figure 36: Urea (54) and thiourea (55) benzo crown receptor for transport and extraction of amino acids.
Figure 37: Crown pyryliums ion receptors 56 for amino acids.
Figure 38: Ditopic sulfonamide bridged crown ether receptor 57.
Figure 39: Luminescent peptide receptor 58.
Figure 40: Luminescent receptor 59 for the detection of D-glucosamine hydrochloride in water/ethanol and lumin...
Figure 41: Guanidinium azacrown receptor 61 for simple amino acids and ditopic receptor 62 with crown ether an...
Figure 42: Chiral bicyclic guanidinium azacrown receptor 63 and similar receptor 64 for the enantioselective t...
Figure 43: Receptors for zwitterionic species based on luminescent CEAAs.
Figure 44: 1,10-Azacrown ethers with sugar podand arms and the anticancer agent busulfan.
Figure 45: Benzo-18-crown-6 modified β-cyclodextrin 69 and β-cyclodextrin functionalized with diaza-18-crown-6...
Figure 46: Receptors for colorimetric detection of primary and secondary ammonium ions.
Figure 47: Porphyrine-crown-receptors 72.
Figure 48: Porphyrin-crown ether conjugate 73 and fullerene-ammonium ion guest 74.
Figure 49: Calix[4]arene (75a), homooxocalix[4]arene (75b) and resorcin[4]arene (75c) compared (R = H, alkyl c...
Figure 50: Calix[4]arene and ammonium ion guest (R = H, alkyl, OAcyl etc.), possible binding sites; A: co-ordi...
Figure 51: Typical guests for studies with calixarenes and related molecules.
Figure 52: Lower rim modified p-tert-butylcalix[5]arenes 82.
Figure 53: The first example of a water soluble calixarene.
Figure 54: Sulfonated water soluble calix[n]arenes that bind ammonium ions.
Figure 55: Displacement assay for acetylcholine (3) with a sulfonato-calix[6]arene (84b).
Figure 56: Amino acid inclusion in p-sulfonatocalix[4]arene (84a).
Figure 57: Calixarene receptor family 86 with upper and lower rim functionalization.
Figure 58: Calix[6]arenes 87 with one carboxylic acid functionality.
Figure 59: Sulfonated calix[n]arenes with mono-substitution at the lower rim systematically studied on their r...
Figure 60: Cyclotetrachromotropylene host (91) and its binding to lysine (81c).
Figure 61: Calixarenes 92 and 93 with phosphonic acids groups.
Figure 62: Calix[4]arene tetraphosphonic acid (94a) and a double bridged analogue (94b).
Figure 63: Calix[4]arene tetraphosphonic acid ester (92c) for surface recognition experiments.
Figure 64: Calixarene receptors 95 with α-aminophosphonate groups.
Figure 65: A bridged homocalix[3]arene 95 and a distally bridged homocalix[4]crown 96.
Figure 66: Homocalix[3]arene ammonium ion receptor 97a and the Reichardt’s dye (97b) for colorimetric assays.
Figure 67: Chromogenic diazo-bridged calix[4]arene 98.
Figure 68: Calixarene receptor 99 by Huang et al.
Figure 69: Calixarenes 100 reported by Parisi et al.
Figure 70: Guest molecules for inclusion in calixarenes 100: DAP × 2 HCl (101a), APA (101b) and Lys-OMe × 2 HC...
Figure 71: Different N-linked peptido-calixarenes open and with glycol chain bridges.
Figure 72: (S)-1,1′-Bi-2-naphthol calixarene derivative 104 published by Kubo et al.
Figure 73: A chiral ammonium-ion receptor 105 based on the calix[4]arene skeleton.
Figure 74: R-/S-phenylalaninol functionalized calix[6]arenes 106a and 106b.
Figure 75: Capped homocalix[3]arene ammonium ion receptor 107.
Figure 76: Two C3 symmetric capped calix[6]arenes 108 and 109.
Figure 77: Phosphorous-containing rigidified calix[6]arene 110.
Figure 78: Calix[6]azacryptand 111.
Figure 79: Further substituted calix[6]azacryptands 112.
Figure 80: Resorcin[4]arene (75c) and the cavitands (113).
Figure 81: Tetrasulfonatomethylcalix[4]resorcinarene (114).
Figure 82: Resorcin[4]arenes (115a/b) and pyrogallo[4]arenes (115c, 116).
Figure 83: Displacement assay for acetylcholine (3) with tetracyanoresorcin[4]arene (117).
Figure 84: Tetramethoxy resorcinarene mono-crown-5 (118).
Figure 85: Components of a resorcinarene based displacement assay for ammonium ions.
Figure 86: Chiral basket resorcin[4]arenas 121.
Figure 87: Resorcinarenes with deeper cavitand structure (122).
Figure 88: Resorcinarene with partially open deeper cavitand structure (123).
Figure 89: Water-stabilized deep cavitands with partially structure (124, 125).
Figure 90: Charged cavitands 126 for tetralkylammonium ions.
Figure 91: Ditopic calix[4]arene receptor 127 capped with glycol chains.
Figure 92: A calix[5]arene dimer for diammonium salt recognition.
Figure 93: Calixarene parts 92c and 129 for the formation molecular capsules.
Figure 94: Encapsulation of a quaternary ammonium cation by two resorcin[4]arene molecules (NMe4+@[75c]2 × Cl−...
Figure 95: Encapsulation of a quaternary ammonium cation by six resorcin[4]arene molecules (NMe3D+@[130]6 × Cl−...
Figure 96: Structure and schematic of cucurbit[6]uril (CB[6], 131a).
Figure 97: Cyclohexanocucurbit[6]uril (CB′[6], 132) and the guest molecule spermine (133).
Figure 98: α,α,δ,δ-Tetramethylcucurbit[6]uril (134).
Figure 99: Structure of the cucurbituril-phthalhydrazide analogue 135.
Figure 100: Organic cavities for the displacement assay for amine differentiation.
Figure 101: Displacement assay methodology for diammonium- and related guests involving cucurbiturils and some ...
Figure 102: Nor-seco-Cucurbituril (±)-bis-ns-CB[6] (140) and guest molecules.
Figure 103: The cucurbit[6]uril based complexes 141 for chiral discrimination.
Figure 104: Cucurbit[7]uril (131c) and its ferrocene guests (142) opposed.
Figure 105: Cucurbit[7]uril (131c) guest inclusion and representative guests.
Figure 106: Cucurbit[7]uril (131c) binding to succinylcholine (145) and different bis-ammonium and bis-phosphon...
Figure 107: Paraquat-cucurbit[8]uril complex 149.
Figure 108: Gluconuril-based ammonium receptors 150.
Figure 109: Examples of clefts (151a), tweezers (151b, 151c, 151d) and clips (151e).
Figure 110: Kemp’s triacid (152a), on example of Rebek’s receptors (152b) and guests.
Figure 111: Amino acid receptor (154) by Rebek et al.
Figure 112: Hexagonal lattice designed hosts by Bell et al.
Figure 113: Bell’s amidinium receptor (156) and the amidinium ion (157).
Figure 114: Aromatic phosphonic acids.
Figure 115: Xylene phosphonates 159 and 160a/b for recognition of amines and amino alcohols.
Figure 116: Bisphosphonate recognition motif 161 for a colorimetric assay with alizarin complexone (163) for ca...
Figure 117: Bisphosphonate/phosphate clip 164 and bisphosphonate cleft 165.
Figure 118: N-Methylpyrazine 166a, N-methylnicotinamide iodide (166b) and NAD+ (166c).
Figure 119: Bisphosphate cavitands.
Figure 120: Bisphosphonate 167 of Schrader and Finocchiaro.
Figure 121: Tweezer 168 for noradrenaline (80b).
Figure 122: Different tripods and heparin (170).
Figure 123: Squaramide based receptors 172.
Figure 124: Cage like NH4+ receptor 173 of Kim et al.
Figure 125: Ammonium receptors 174 of Chin et al.
Figure 126: 2-Oxazolin-based ammonium receptors 175a–d and 176 by Ahn et al.
Figure 127: Racemic guest molecules 177.
Figure 128: Tripods based on a imidazole containing macrocycle (178) and the guest molecules employed in the st...
Figure 129: Ammonium ion receptor 180.
Figure 130: Tetraoxa[3.3.3.3]paracyclophanes 181 and a cyclophanic tetraester (182).
Figure 131: Peptidic bridged paraquat-cyclophane.
Figure 132: Shape-selective noradrenaline host.
Figure 133: Receptor 185 for binding of noradrenaline on surface layers from Schrader et al.
Figure 134: Tetraphosphonate receptor for binding of noradrenaline.
Figure 135: Tetraphosphonate 187 of Schrader and Finocchiaro.
Figure 136: Zinc-Porphyrin ammonium-ion receptors 188 and 189 of Mizutani et al.
Figure 137: Zinc porphyrin receptor 190.
Figure 138: Zinc porphyrin receptors 191 capable of amino acid binding.
Figure 139: Zinc-porphyrins with amino acid side chains for stereoinduction.
Figure 140: Bis-zinc-bis-porphyrin based on Tröger’s base 193.
Figure 141: BINAP-zinc-prophyrin derivative 194 and it’s guests.
Figure 142: Bisaryl-linked-zinc-porphyrin receptors.
Figure 143: Bis-zinc-porphyrin 199 for diamine recognition and guests.
Figure 144: Bis-zinc-porphyrin crown ether 201.
Figure 145: Bis-zinc-porphyrin 202 for stereodiscrimination (L = large substituent; S = small substituent).
Figure 146: Bis-zinc-porphyrin[3]rotaxane and its copper complex and guests.
Figure 147: Dien-bipyridyl ligand 206 for co-ordination of two metal atoms.
Figure 148: The ligand and corresponding tetradentate co-complex 207 serving as enantioselective receptor for a...
Figure 149: Bis(oxazoline)–copper(II) complex 208 for the recognition of amino acids in aqueous solution.
Figure 150: Zinc-salen-complexes 209 for the recognition tertiary amines.
Figure 151: Bis(oxazoline)–copper(II) 211 for the recognition of amino acids in aqueous solution.
Figure 152: Zn(II)-complex of a C2 terpyridine crown ether.
Figure 153: Displacement assay and receptor for aspartate over glutamate.
Figure 154: Chiral complex 214 for a colorimetric displacement assay for amino acids.
Figure 155: Metal complex receptor 215 with tripeptide side arms.
Figure 156: A sandwich complex 216 and its displaceable dye 217.
Figure 157: Lanthanide complexes 218–220 for amino acid recognition.
Figure 158: Nonactin (221), valinomycin (222) and vancomycin (223).
Figure 159: Monesin (224a) and a chiral analogue for enantiodiscrimination of ammonium guests (224b).
Figure 160: Chiral podands (226) compared to pentaglyme-dimethylether (225) and 18-crown-6 (4).
Figure 161: Lasalocid A (228).
Figure 162: Lasalocid derivatives (230) of Sessler et al.
Figure 163: The Coporphyrin I tetraanion (231).
Figure 164: Linear and cyclic peptides for ammonium ion recognition.
Figure 165: Cyclic and bicyclic depsipeptides for ammonium ion recognition.
Figure 166: α-Cyclodextrin (136a) and novocaine (236).
Figure 167: Helical diol receptor 237 by Reetz and Sostmann.
Figure 168: Ammonium binding spherand by Cram et al. (238a) and the cyclic[6]metaphenylacetylene 238b in compar...
Figure 169: Receptor for peptide backbone and ammonium binding (239).
Figure 170: Anion sensor principle with 3-hydroxy-2-naphthanilide of Jiang et al.
Figure 171: 7-bromo-3-hydroxy-N-(2-hydroxyphenyl)naphthalene 2-carboxamide (241) and its amine binding.
Figure 172: Naturally occurring catechins with affinity to quaternary ammonium ions.
Figure 173: Spiropyran (244) and merocyanine form (244a) of the amino acid receptors of Fuji et al.
Figure 174: Coumarin aldehyde (245) and its iminium species with amino acid bound (245a) by Glass et al.
Figure 175: Coumarin aldehyde appended with boronic acid.
Figure 176: Quinolone aldehyde dimers by Glass et al.
Figure 177: Chromogenic ammonium ion receptors with trifluoroacetophenone recognition motifs.
Figure 178: Chromogenic ammonium ion receptor with trifluoroacetophenone recognition motif bound on different m...
Novel banana-discotic hybrid architectures
- Hari Krishna Bisoyi,
- H. T. Srinivasa and
- Sandeep Kumar
Beilstein J. Org. Chem. 2009, 5, No. 52, doi:10.3762/bjoc.5.52
- switched in external electric fields. Various new applications of these materials include nonlinear optics, flexoelectricity, photoconductivity, molecular electronics and the design of biaxial nematic phases [8][9]. In addition to various banana phases, these mesogens also display classical nematic
Graphical Abstract
Scheme 1: Synthesis of banana bridged discotic dimer. Reagents and conditions; (i) Br(CH2)12Br, Cs2CO3, MEK, ...
Scheme 2: Synthesis of banana-discotic dimers.
A convenient method for preparing rigid-core ionic liquid crystals
- Julien Fouchet,
- Laurent Douce,
- Benoît Heinrich,
- Richard Welter and
- Alain Louati
Beilstein J. Org. Chem. 2009, 5, No. 51, doi:10.3762/bjoc.5.51
- fully assess the prospects for using these molecules in molecular electronics. We intend also to introduce different length tails in order to obtain room temperature ionic liquid crystals, aswell as to explore use of the coupling reaction between imidazole and other aromatics and heterocycles to tune
Graphical Abstract
Scheme 1: 1-[4-(dodecyloxy)phenyl]-3-methyl-1H-imidazol-3-ium mesogenic salts.
Scheme 2: Synthesis of the imidazole A. Reaction conditions: (i) aryl iodide (1.37 mmol), imidazole (1.69 mmo...
Scheme 3: Synthesis of methyl imidazolium 1a. Reaction conditions: (i) MeI in sealed tube, 54 h at RT.
Figure 1: ORTEP view of compound 1a with partial labelling. The closest molecules are represented (with lower...
Figure 2: Packing diagram of compound 1a in projection in the (b,c) lattice plane. Large spheres represent th...
Scheme 4: Anion metathesis in water/CH2Cl2 as solvent.
Figure 3: Spectra of absorption (red line) and emission (blue line) of 1a.
Figure 4: TGA measurements of the compounds 1a–e (rate 10 °C·min−1, in air).
Figure 5: Phase transition temperatures of compounds 1a–e.
Figure 6: Powder X-ray diffraction pattern of compound 1a in the liquid crystal state (T = 120 °C).
Figure 7: The melting process involves the ruffling of the ionic sublayer. In the smectic phase, the ruffling...
Figure 8: Comparison of the molecular area S and of the ionic sublayer thickness dc (including mesogenic segm...
Figure 9: Variation with the counter-ion of the molecular area S and of the ionic sublayer thickness dc (incl...
Figure 10: Cyclic voltammogram of 1a in CH3CN (0.1 M NBu4PF6): (i), (ii) cathodic and anodic range of the volt...
