4-Alkoxydithiobenzoic acids

Figure 9 Structures of 4-alkoxydithiobenzoic acid and 4-alkoxytrithiobenzoic acid.

The linear dichroism of nickel(II), palladium(II) and zinc(II) complexes of mesomorphic 4-alkoxydithiobenzoic acids has been investigated in the commercial eutectic mixture of cyanobiphenyls and cyanoterphenyls, E7 (from Merck) for the palladium(II) complexes and in the commercial mixture of cyanobicyclohexanes, ZLI2830 (from Merck) for the nickel(II) and zinc(II) complexes (Figure 2.12).For the nickel(II) and palladium(II) complexes both a ligand-based transition and a charge-transfer band (MLCT) were observed, whereas only a ligand-based transition was present for the zinc(II) complexes. These complexes had a much lower solubility in the liquid crystal host matrix than the dithiolene... 

Most of the work with calamitic dithiocarboxylates has centered on studies on metal complexes of 4-alkoxydithiobenzoic acids. Complexes of the empirical formula [M( -odtb)2] were synthesized for M = Ni, Pd, and Zn (196) and square-planar gold(III) complexes showing SmA phases ([AuX2( -otdb)] X = Cl, Br, Me) were also described. 

Most of the work on dithiocarboxylates have been centered on metal complexes of 4-alkoxydithiobenzoic acids (abbreviated to n-odtbH) 34. 

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