New RM734-like fluid ferroelectrics enabled through a simplified protecting group free synthesis

Abstract

We report a novel and simplified synthetic procedure for making analogues of the widely studied ferroelectric nematogen RM734. Our new procedure focuses on building materials starting from the nitro-terminus and eschewing protecting groups, in contrast to previously reported syntheses. This new synthetic approach confers two principal advantages: firstly, the synthesis of the variants described herein is expedient, being a single step as opposed to three or more via the classical route. Secondly, by forgoing the use of benzyl groups as utilised in the original synthesis we can include functionality that is incompatible with hydrogenolysis conditions (e.g. olefins, late halogens, unsaturated heterocycles). Several of the RM734-like materials we report exhibit ferroelectric nematic phases, and we rationalise the behaviour of these materials with aid of electronic structure calculations, potential energy surface scans and atomistic molecular dynamics simulations.