Mesomorphic Metallo-Dendrimers Based on the Metal−Metal Bonded Ru₂(CO)₄ Sawhorse Unit

Abstract

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.

Liquid‐Crystalline Thiol‐ and Disulfide‐Based Dendrimers for the Functionalization of Gold Nanoparticles. Preliminary Communication

“…We designed mesomorphic materials by functionalizing [60]fullerene (nematic, chiral nematic, smectic A, smectic C, columnar phases) [9], [60]fullerene -ferrocene dyads (smectic A phase) [10], and diruthenium clusters (nematic and smectic A phases) [11] with liquid-crystalline dendrimers. The nature of the mesophases and the supramolecular organization within the liquid-crystal state could be controlled via the structure of the mesomorphic units, and the structure and size (generation) of the dendrons.…”

[60]Fullerene-based liquid crystals acting as acid-sensitive fluorescent probes

“…The synthesis of 1a and 1b (Scheme 1) required the reaction of second-(4a) 6 or third-generation (4b) 7 dendron carrying a carboxylic acid function ( Fig. 1) with thionyl chloride in CH 2 Cl 2 to prepare the corresponding acid chlorides followed by their in situ condensation with fulleropyrrolidine 2 in CH 2 Cl 2 .…”

Sawhorse-type diruthenium tetracarbonyl complexes

“…(4) and (5). By this method not only a large variety of carboxylato complexes of the type Ru 2 (CO) 4 (OOCR) 2 L 2 became accessible (XYH = RCOOH) [12][13][14][15], but also carboxamido complexes (XYH = RCONH 2 ) [16,17], pyrazolato complexes (XYH = C 3 R 1 R 2 R 3 N 2 H) [18,19], oxinato complexes (XYH = R 1 R 2 CNOH) [20] and sulfonato complexes (XYH = R 2 SO 3 H) [21], all with the typical Ru 2 (CO) 4 sawhorse structure.…”

“…30. Mesomorphic Ru2(CO)4(OOCR)2L2 complexes containing mesogenic dendritic substituents in the carboxylato bridges [14]. • C (left) and proposed supramolecular organization (right) [14].…”

“…Mesomorphic Ru2(CO)4(OOCR)2L2 complexes containing mesogenic dendritic substituents in the carboxylato bridges [14]. • C (left) and proposed supramolecular organization (right) [14]. 2 ] n have been found to catalyze in dichloromethane the intramolecular degradation of ␣-diazo acetamides to give lactams [Eqs.…”