Dinuclear ruthenium complexes containing the stable metal−metal bonded Ru2(CO)4 sawhorse unit with two dendritic carboxylato bridges have been synthesized and characterized. All complexes Ru2(CO)4(O2CR)2L2 (R = R1, R2, R3) containing cyanobiphenyl-based poly(arylester) dendrons of first (R1), second (R2), and third (R3) generation and triphenylphosphine, pyridine, or 4-picoline ligands L proved to be mesomorphic, giving rise to smectic A or smectic A and nematic phases. The supramolecular organization within the smectic A phase is governed by the nature and structure of the mesogenic units and dendritic core. Such materials are of interest for the design of catalytically active anisotropic fluids.

Diastereoselective ortho-hydroxymethylation of (R)-(1-ferrocenylethyl)dimethylamine and Brønsted-acid-mediated nucleophilic substitution with phenyl(trifluoromethyl)phosphane affords an epimeric mixture of P-stereogenic aminephosphanes 4a and 4b, which are readily separated by crystallization from methanol. Subsequent substitution of the dimethylamino group with diphenylphosphane occurs without epimerization, yielding novel bis(phosphanes) 1a and 1b.

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