(S)‐Isoleucine and (R)‐2‐octanol as chiral precursors of new chiral liquid crystalline thiadiazoles: synthesis, mesomorphic and ferroelectric properties

New chiral Schiff bases with a 1,3,4‐thiadiazole unit in the rigid core were synthesized (SB1–SB4). These compounds contain a chiral chain derived from (S)‐isoleucine and (R)‐2‐octanol. Their liquid crystalline properties were studied by polarizing optical microscopy, differential scanning calorimetry and X‐ray diffraction. Thereby it was found that most of the new compounds exhibit a chiral Smectic C phase. A study of the ferroelectric properties is described.