Transition Metals Complexed to Ordered Mesophases1. Synthesis and Mesomorphic Properties of a Homologous Series of N-(4-Dodecyloxysalicylidene)-4′-Alkylanilines Complexed to Palladium(II)

The new [N-(4-dodecyloxysalicylidene)4′-C n H2n + 1-aniline] palladium (II) derivatives, (R n L)2Pd, (1–6: n = 1–4,6,8 respectively) have been synthetized and their mesomorphic properties investigated by optical microscopy, DSC and X-ray diffraction measurements. Complexes 1–6, but 4, display a monotropic (1,5) or enantiotropic (2,3,6) smectic A mesophase. In 1–6 the geometry of the metal coordination sphere is square planar and with reference to homologous (R n L)2M compounds the mesomorphism of 1–6 appears at temperatures higher than for (R n L)2VO (distorted square pyramidal) or (R n L)2Cu (distorted square planar).