Synthesis of 5-Cyanotroponoids with a Polyalkoxybenzoyloxy and a Polyalkoxybenzoylamino Substituent at C-2

Abstract

We prepared 5-cyanotroponoids with a forked mesogen at the C'2 position. 2-(3,4-Dialkoxybenzoyloxy)-5-cyanotroponoids showed a monotropic smectic A phase with lower clearing points than those of the corresponding 2-(4-alkoxybenzoyloxy) derivatives, while 2-(3,4,5-trialkoxybenzoyloxy) derivatives showed columnar phases. The corresponding benzenoids, however, were non-mesomorphic. Furthermore, 2-(3,4,5-trialkoxybenzoylamino)-5-cyanotroponoids were able to gelate alcohols and hydrocarbons. Thus, troponoid cores preferred to induce mesomorphic properties. This is due to the presence of the carbonyl group, which played as a lateral dipole group.