Optically active 2-methyl 1,3-propanediol derivatives, liquid crystal compositions comprising them and optical switching element.

摘要

A compound represented by formula (I) <CHEM> wherein R<1> represents an alkyl group having 1 to 20 carbon atoms or an alkoxy group having from 1 to 20 carbon atoms, R<2> represents an alkyl group having from 1 to 15 carbon atoms, an alkanoyl group having from 2 to 15 carbon atoms, an alkoxycarbonyl group having from 2 to 15 carbon atoms, an alkoxyalkyl group having from 2 to 15 carbon atoms, an alkoxyalkanoyl group having from 3 to 15 carbon atoms, a halogenated alkyl group having from 1 to 15 carbon atoms or a halogenated alkanoyl group having from 2 to 15 carbon atoms, and the alkyl moiety in R<1> and R<2> is straight or branched; A and B each represents <CHEM> wherein X represents a halogen atom, a cyano group or a trifluoromethyl group; and the asterisk mark * indicates that the carbon atom provided with * is an asymmetrical carbon atom, a liquid crystal composition comprising at least one compound of formula (I), and an optical switching element using as a liquid crystal a liquid crystal composition comprising at least one compound of formula (I) are disclosed. The compound of formula (I) has a property to increase the degree of spontaneous polarization and is useful as a component of a liquid crystal composition.