Synthesis and mesomorphism of modified 2,5-Di(4-dodecoxyphen-1-yl)-c-cyclopentene-pyridines

Herein, we report on a new series of mesomorphic compounds synthesised by directional functionalisation of 2,5-di(4-dodecoxyphen-1-yl-c-cyclopentene-pyridine) on the c-cyclopentene moiety. The first functionalisation of the starting compound gave rise to a racemic product modified with a hydroxyl group on the fused cyclopentene ring. Further oxidation of this alcohol to a prochiral ketone and subsequent enantioselective reduction back to the alcohol afforded a new chiral alcohol. Further, the hydroxyl group of the chiral alcohol could be substituted by fluorine in a S_N2 reaction, leading to a chiral compound with enantiomeric excess (ee) of 66% and chiral nematic liquid-crystalline (LC) phase.