Functional properties of metallomesogens modulated by molecular and supramolecular exotic arrangements

• Alessandra Crispini,
• Mauro Ghedini and
• Daniela Pucci

Beilstein J. Org. Chem. 2009, 5, No. 54, doi:10.3762/bjoc.5.54

• single molecule to supramolecular network, confirming that metal coordination provides a helpful tool for obtaining multifunctional soft materials. Keywords: coordination complexes; functionality; liquid crystals; metallomesogens; Introduction Recent interest in designing novel soft and functional

• intramolecular interactions [25][26][27][28][29][30]. The high level of functionality integrated into molecular-based electronic systems obtained by incorporating metal centres into selected organic structures [31] supports the design of metal-containing liquid crystals (metallomesogens) as an effective and

• helpful way to expand of the traditional range of technological applications of liquid crystals [32][33][34][35][36][37]. We have been involved for long time in the field of metallomesogens with the synthesis of cyclopalladated rod-like complexes starting from mesogenic azo and azoxybenzenes, confirming

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

• crystalline property probably because of the incompatibility of the bent-core with the discotic core. Keywords: bent-core; dimer; discotic; triphenylene; Introduction Liquid crystals are unique functional self-organized soft materials which possess order and dynamics. Recently, banana liquid crystals or

• , smectic and columnar phases. On the other hand, the unique geometry of the columnar mesophase formed by discotic liquid crystals is of great importance not only as models for the study of one-dimensional charge and energy migration in organized systems but also as functional materials for device

• and self-healing of defects owing to their dynamic nature. Furthermore, there has been considerable interest in the field of non-conventional low molar mass liquid crystals, especially in liquid crystal dimers because of their interesting mesomorphic properties. Liquid crystal oligomers serve as ideal

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

• , differential scanning calorimetry and X-ray diffraction. In addition its lamellar crystal structure, electrochemical behaviour and UV (absorption and emission) properties are reported. Keywords: imidazolium; ionic liquid crystals; Ullman reaction; Introduction Over the past decade extensive studies of ionic

• /hydrophobicity…). Important emerging applications include those in separation and extraction processes, and in various electrochemical devices, such as lithium ion batteries, fuel cells, and capacitors, as well as in synthesis and catalysis [1][2][3][4][5]. Liquid crystals are characterised by both mobility and

• governs the formation of a multitude of supramolecular architectures depending on the temperature (thermotropic liquid crystals) and/or of the solvent (lyotropic liquid crystals) [7][8]. In the case of the thermotropic liquid crystals the arrangements give rise to nematic phases (molecules are aligned

Chiral amplification in a cyanobiphenyl nematic liquid crystal doped with helicene-like derivatives

• Alberta Ferrarini,
• Silvia Pieraccini,
• Stefano Masiero and
• Gian Piero Spada

Beilstein J. Org. Chem. 2009, 5, No. 50, doi:10.3762/bjoc.5.50

• , allows us to extend our knowledge of the molecular origin of the chirality amplification in liquid crystals and to confirm the simple relationship “molecular P-helicity” → “cholesteric P-handedness” for helical-shaped helicene-like derivatives. Keywords: chirality; cholesteric; helical twisting power

• ; helicene; nematic liquid crystal; Surface Chirality model; Introduction Nematic liquid crystals (LCs) are fluid phases formed by anisometric molecules which, though free to rotate as in ordinary liquids, are preferentially aligned along a common axis, called director. The addition of a chiral non-racemic

• variously distributed around the molecular core, allows us to extend our knowledge of the molecular origin of the chirality amplification in liquid crystals. Results and Discussion The enantioselective synthesis as well as the configuration assignment of enantiopure dihydro[5]helicene quinones or

Synthesis of mesogenic phthalocyanine-C₆₀ donor–acceptor dyads designed for molecular heterojunction photovoltaic devices

• Yves Henri Geerts,
• Olivier Debever,
• Claire Amato and
• Sergey Sergeyev

Beilstein J. Org. Chem. 2009, 5, No. 49, doi:10.3762/bjoc.5.49

• example of LC phthalocyanine-C60 dyads. Keywords: donor–acceptor dyad; fullerene; liquid crystals; phthalocyanine; phthalonitrile; Introduction Among sustainable energy technologies, photovoltaic (PV) conversion of solar energy is considered as a promising solution. Although currently the market is

Progress in liquid crystal chemistry

• Sabine Laschat

Beilstein J. Org. Chem. 2009, 5, No. 48, doi:10.3762/bjoc.5.48

• Sabine Laschat Institut für Organische Chemie, Universität Stuttgart, Pfaffenwaldring 55, D-70569 Stuttgart, Germany 10.3762/bjoc.5.48 Since their discovery in 1888 by the botanist Friedrich Reinitzer, who studied the melting behavior of cholesteryl benzoates, liquid crystals have developed from

• a mere curiosity to a highly interdisciplinary research field, with LC displays being the most important application to date [1][2]. However, besides the use of thermotropic liquid crystals for display technology many other applications will probably be on the market in the near future, such as

• diverse topics such as phthalocyanine-fullerene hybrid materials for photovoltaic devices, functional metallomesogens, coaxial electrospinning of liquid crystal-containing microfibers, banana-discotic hybrid systems, ionic liquid crystals, relations between molecular length distribution and formation of

DBFOX- Ph/metal complexes: Evaluation as catalysts for enantioselective fluorination of 3-(2-arylacetyl)-2-thiazolidinones

• Takehisa Ishimaru,
• Norio Shibata,
• Dhande Sudhakar Reddy,
• Takao Horikawa,
• Shuichi Nakamura and
• Takeshi Toru

Beilstein J. Org. Chem. 2008, 4, No. 16, doi:10.3762/bjoc.4.16

• electrophilic fluorination represents an important and straightforward strategy for C-F bond formation at a carbon stereocenter, providing easy access to chiral fluoro-organic compounds [1][2]. Due to the significance of chiral fluoro-organic compounds, such as fluorinated quinolones [3][4] and liquid crystals

Themed series in organo- fluorine chemistry

• David O'Hagan

Beilstein J. Org. Chem. 2008, 4, No. 11, doi:10.3762/bjoc.4.11

• ]. Organo-fluorine compounds have also found a significant role in soft materials chemistry such as liquid crystals, photoresist polymers and self assembling monolayers [3]. Allied to this breadth of activity is a steady development in the number and range of fluorination reagents and methodologies. DAST

Shape- persistent macrocycle with intraannular alkyl groups: some structural limits of discotic liquid crystals with an inverted structure

• Sigurd Höger,
• Jill Weber,
• Andreas Leppert and
• Volker Enkelmann

Beilstein J. Org. Chem. 2008, 4, No. 1, doi:10.1186/1860-5397-4-1

• defined surfaces [1][2][3][4][5][6][7][8]. Furthermore, shape-persistent macrocycles are interesting mesogens for discotic liquid crystalline materials [9][10][11][12]. The common design principle of conventional discotic liquid crystals (LCs) is a more or less rigid core (disk-like or macrocyclic) with

• parameter to fine tune the thermal behavior of discotic liquid crystals with an inverted structure. This parameter is absent in conventional discotic liquid crystals. As expected, longer adaptable alkyl substituents (compared to 1) decrease the melting point of the macrocycles but at the same time also

• /conts/retrieving.html, or from the Cambridge Crystallographic Data Centre, 12 Union Road, Cambridge CB2 1EZ, UK; fax: (+44)1223-336033; or email: deposit@ccdc.cam.ac.uk. a) Design principle for common discotic liquid crystals; b) Design principle for discotic liquid crystals with an inverted structure

A convenient catalyst system for microwave accelerated cross- coupling of a range of aryl boronic acids with aryl chlorides

• Matthew L. Clarke,
• Marcia B. France,
• Jose A. Fuentes,
• Edward J. Milton and
• Geoffrey J. Roff

Beilstein J. Org. Chem. 2007, 3, No. 18, doi:10.1186/1860-5397-3-18

• biaryl products (see Supporting Information File 1 for experimental data). There has been some interest in the cross-coupling of fluorinated nucleophiles due to the application of fluoroaryl substituents in medicinal chemistry and in liquid crystals. [30][31][32][33][34] The Buchwald group recently