摘要 |
An optically active compound of the following general formula (1) useful as a chiral dopant, and use thereof,wherein each of X and Y is independently a hydrogen atom or a fluorine atom, R is (C2H5)2CHCH2C*H(CH3)- or Ph-C*H(CH3)-, A is -Ph(W)-COO-Ph-, -Ph-Ph-COO-, -Cy-COO-Ph-, -Ph(W)-OOC-Ph-COO-, -Ph(W)-OOC-Cy-COO-, -Ph(W)-OOC-Np-COO- or -Np-OOC-, in which Ph- is a phenyl group, -Ph- is a 1,4-phenylene group, -Ph(W)- is -Ph- or monofluoro substituted -Ph-, Cy- is a trans-1,4-cyclohexylene group and -Np- is a 2,6-naphthylene group, and C* is an asymmetric carbon.The optically active compound of the present invention has a large helical twisting power (HTP) of at least 14 and suitably has the property that its induced helical pitch decreases in length with an increase in temperature, so that it has an excellent value as a chiral dopant for a nematic liquid crystal composition.
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