Masashi Osawa

Synthesis and properties of optically active 1,3-diols and their derivatives as chiral dopants for ferroelectric liquid crystals

Abstract New chiral dopants β-hydroxy ketones 1, 1,3-diols 2, 1,3-dioxanes 3 and 1,3-dioxan-2-ones 4 were designed and synthesized. Reaction of (R)-1,2-epoxyoctane with carbanions derived from 2-(4-substituted phenyl)-1,3-dithianes followed by hydrolysis of the resulting hydroxy dithianes afforded 1. Reduction of 1 gave the diols 2, which yielded 3 upon acetalization and 4 upon carbonation. The syn isomers of 2, 3, and 4 exhibited larger spontaneous polarizations, when applied as chiral dopants, than the anti isomers or hydroxy ketones 1.

The adsorption of CO and hydrogen on reduced molybdenum catalysts used for CO hydrogenation

Abstract The adsorption of CO and H 2 on reduced Mo catalysts derived from the reduction of various heteropoly molybdates has been studied. Both CO and H 2 were adsorbed on a well-reduced metallic Mo surface. However, only a portion of the surface was reduceable to the zero valent state and was thus available for adsorption. Turnover frequencies for CO hydrogenation calculated on the basis of CO adsorption are comparable to those observed on Ni even though Mo is reported to be a poor catalyst for CO hydrogenation. The effect of the countercations of HPMo on the selectivity for olefin formation is explained by considering the relative affinity of the surface for CO and hydrogen. The results of TPD and TPR experiments suggest that CO is adsorbed nondissociatively. The surface-CO bond appears to be considerably weaker than that observed for noble metals.

Components for host mixtures of FLC

Abstract Some liquid crystal materials are presented and discussed useful to improve the physical properties of a host mixture for FLC, for example, their temperature range, phase sequences, viscosity and response time.

Synthesis and properties of new optically active γ-lactones as chiral dopants for ferroelectric liquid crystals

Optically active α-aryl-γ-alkyl-γ-lactones were synthesized through the reaction of chiral 1,2-epoxyalkanes with the carbanion derived from 4-methoxyphenylacetonitrile or 4-methoxyphenylacetic acid and shown to be good chiral dopants for ferroelectric liquid crystals.

Correlation between absolute configuration of benzylic chiral centre and sign of spontaneous polarization of chiral dopants for ferroelectric liquid crystals

The absolute configuration of a polar-group-substituted benzylic chiral carbon of a chiral dopant for ferroelectric liquid crystals is found to be predictable by the sign of spontaneous polarization of the ferroelectric liquidcrystalline mixtures containing the chiral dopant.