Novel ferrocene diesters with liquid-crystal properties

Bhatt, J.; Fung, B. M.; Nicholas, Kenneth M.; Poon, Chi‐Duen

doi:10.1039/c39880001439

Cited by 51 publications

(12 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The early period of this research mainly was aimed at bringing ferrocene to the polymer because of its excellent aromatic character and thermal stability at temperatures over 500°C. Several reports [61][62][63][64][65][66] are dealing with ferrocene esters. It is simply a part of the mesogen.…”

Section: Ferrocene-containing Liquid Crystalline Polymersmentioning

confidence: 99%

See 1 more Smart Citation

Organometallic Ferrocene- and Phosphorus-Containing Polymers: Synthesis and Characterization

Hussein

Asiri

2012

Designed Monomers and Polymers

View full text Add to dashboard Cite

The inclusion of organometallic units into polymeric structures has attracted much attention in different fields according to the nature and behaviour of the inserted metal. Moreover, the discovery of organometallic polymers and their structural characterization initiated an explosive rebirth of organometallic chemistry. Organometallic moieties are in or pendent to the polymer backbone and examine some of the uses of the emergent metallocene polymers, and new uses are still being found for these remarkable organometallic moieties. This review gives a simple introduction to variable organometallic molecules and their characteristics. This review will focus on the syntheses and characterization of organometallic polymers, including ferrocene-and phosphorus-containing polymers. A general overview on ferrocene polymers with a special attention to ferrocene-containing liquid crystalline polymers (including a ferrocene moiety in the main chain, side-chain or dendrimers) and fullerene-ferrocene liquid crystalline polymers is presented. In addition, more details for synthesis and properties of phosphorus-containing polymers are illustrated.

show abstract

Section: Ferrocene-containing Liquid Crystalline Polymersmentioning

confidence: 99%

“…26). Generally, most of the LC ferrocenes have complicated structures, i.e., they have three aromatic rings in the mesogen unit [71,99], and two flexible long chains [100,101]. Such complexity sometimes prevents orderly molecular packing [102][103][104].…”

Section: Ferrocene Moieties In Side-chain Liquid Crystalline Polymersmentioning

confidence: 99%

Organometallic Ferrocene- and Phosphorus-Containing Polymers: Synthesis and Characterization

Hussein

Asiri

2012

Designed Monomers and Polymers

View full text Add to dashboard Cite

show abstract

“…The ferrocene moiety in the compound, however, is an appendage to a mesogenic unit rather than being in the core of the molecule. We have recently synthesized a series of ferrocene diesters which have the ferrocene moiety at the centre of the molecule [6]. Three of the compounds in this homologous series exhibit mesomorphic properties.…”

Section: Introductionmentioning

confidence: 99%

X-ray diffraction studies of mesomorphic ferrocene diesters

et al. 1989

Self Cite

View full text Add to dashboard Cite

1989) X-ray diffraction studies of mesomorphic ferrocene diesters, Liquid Crystals, 5:1, 285-290,The crystal and molecular structure of 1,l '-bis(4'-pentyloxybiphenyl)ferrocene dicarboxylate ester (1) has been determined by X-ray diffraction at 295 and 160K. The molecule is found to exist at both temperatures in an extended S geometry. The carboxyl groups are essentially coplanar with the cyclopentadienyl rings but almost perpendicular to the attached phenyl ring. Low angle X-ray diffraction of three diesters in the smectic phases were also studied. The results were not very definitive because of the lack of thermal stability for the monotropic phase behaviour. Nevertheless, the layer spacing of about 47 A for one of the compounds at 409K is consistent with the extended S shape conformation.,

show abstract

“…1. Only three ferrocene derivatives from the reported series [14] (n 4 ± 11) show mesomorphic behaviour ( Fig. 1): the compounds with n 5 and 6 exhibit a monotropic smectic C (SmC) phase in a narrow temperature interval, while the compound with n 11 gives rise to a monotropic smectic A (SmA) phase.…”

mentioning

confidence: 97%

“…Historically, the ferrocene 1,1'-diesters bis(4'-alkoxy-[1,1'-biphenyl]-4-yl) ferrocene-1,1'-dicarboxylates were reported as the first mesogenic ferrocene derivatives [14]. X-Ray diffraction studies indicated that these compounds adopt a −transoid× conformation (−S× shape) in the crystalline and mesomorphic states [15], which approximately corresponds to the pseudo-para substitution pattern in paracyclophanes.…”

mentioning

confidence: 98%

Thermotropic Liquid Crystals from Planar Chiral Compounds: [2.2]Paracyclophane as a Mesogen Core

Rozenberg

Popova

Hopf

2002

HCA

View full text Add to dashboard Cite

New thermotropic mesomorphic compounds containing a [2.2]paracyclophane (PC) unit were synthesized and investigated (Scheme). Carboxylic acids were selected as the starting PC building blocks. The influence of structural features on the stability of the mesomorphic phases was studied (Figs. 1 and 2): for this purpose, the structures of the PC-carboxylate unit and the organic fragment of the aryl-ester moiety were varied systematically. Esters derived from PC-monocarboxylic acid did not exhibit liquid-crystalline (LC) properties, while diaryl PC-dicarboxylates favored mesomorphism. Dicarboxylate substituents arranged in the paraposition provided LC phases in a broad temperature range and considerably increased the mesomorphic interval in comparison with that of the structurally related pseudo-para PC derivatives.Introduction. ± Unique physical properties, providing wide application in electrooptic devices and particularly the recent discovery of new mesophases, such as antiferroelectric, ferrielectric, and twist-grain boundary phases, have put chiral liquidcrystalline (LC) materials in the centre of liquid-crystal research [1] [2]. Historically, up to now, most chiral LC compounds contain molecules incorporating a centre of chirality. More recently, compounds with planar and axial chirality are beginning to attract the growing interest of researchers dealing with LC materials. The unique geometry of this type of compounds provides a rigid interaction between the origin of the symmetry-breaking chirality and the mesogenic unit, thus resulting in a definite fixation of the source of chirality in a LC matrix.In principle, planar chirality could drastically change the physical properties of the resultant LC material: 1) In terms of molecular structure, a rigid steric coupling between the transverse dipole, chiral centre, and the mesogen rod should maximize the local ferroelectric polarization [3], allowing consideration of the above compounds as possible chiral dopants for ferroelectric compositions, which are able to confer a high value of spontaneous polarization (P s ) to the achiral host [4]. 2) Electro-optical effects exhibited by LC materials such as electroclinic effects or nonlinear optical (NLO) properties are expected to be larger for compounds with rigid interaction between the chiral and optical portions of the molecule [5].However, the bulkiness of the structural units necessary to realize an axis or a plane of chirality significantly disturbs the desired rigid rod-like shape of the molecule, thus creating a serious obstacle to achieving stable mesomorphic properties. So far, only a

show abstract

Novel ferrocene diesters with liquid-crystal properties

Cited by 51 publications

References 0 publications

Organometallic Ferrocene- and Phosphorus-Containing Polymers: Synthesis and Characterization

Organometallic Ferrocene- and Phosphorus-Containing Polymers: Synthesis and Characterization

X-ray diffraction studies of mesomorphic ferrocene diesters

Thermotropic Liquid Crystals from Planar Chiral Compounds: [2.2]Paracyclophane as a Mesogen Core

Contact Info

Product

Resources

About