Synthesis of Optically Active 2-M4ethylchroman Derivatives and Application to Chiral Dopants for Nematic Liquid Crystals

摘要

Chiral 2-methylchroman-2-carboxylic acid derivatives were prepared as new chiral dopants for nematic liquid crystals.The starting material,optically activ3e 6-benzyloxy-2-methylchroman-2-carboxylic acid,was newly synthesized as a rigid core structure and resolved by a diastereomeric salt formation method.Its absolute configuration was determined by comparing its circular dichroism spectrum with that of the commercially available (S)-6-hydroxy-2,5,7,8-tetramethyl-chroman-2-carboxylic acid derivative.The helical twisting power of the new dopants was determined and the relationship between their functional groups and flexible terminal structures was studied.