Optically active compound and nematic liquid crystal composition containing the compound

Abstract

An optically active compound of the following general formula (1), wherein A is —C≡C— or —COO—, each of R1 and R2 is independently CnH2n+1—, (C2H5)2CHCH2C*H(CH3)OOC—, CmH2m+1C*H(CH3)OOC— or C6H5C*H(CH3)OOC— in which n is an integer of 2 to 5, m is an integer of 5 to 9, C6H5— is phenyl group, and C* is an asymmetric carbon, provided that there is no case where R1 and R2 are together CnH2n+1— or C6H5C*H(CH3)OOC— and that when both R1 and R2 are CmH2m+1C*H(CH3)OOC—, m in CmH2m+1C*H(CH3)OOC— represented by R1 and m in CmH2m+1C*H(CH3)OOC— represented by R2 may be different integers. The optically active compound of the present invention is excellently valuable as a chiral dopant since it has properties that its helical twisting power (HTP) is at least 9, that a helical pitch induced decreases with an increase in temperature and further that its birefringence (Δn) is large.

Dependencies are inferred from the claim text.