Metalla-macrocycles

One of the most successful approaches to the synthesis of metalla-supramolecular systems has been by templated self-assembly processes. Most of the templating agents used by synthetic chemists are either cationic or neutral species. Anions, on the other hand, have only fairly recently been successfully utilized as templates. The new metalla-macrocycles [Pd2Ni2(atu)4(PPh3)4X]3+ (atu = deprotonated amidinothiourea, X = C1, Br, I) have been prepared using anion templated syntheses. Only in the presence of each of these three halides are the metalla-macrocycles... 

Fig. 2 Anion-templated metalla-macrocycles and silver-alkynyl cages View this art in color ut www.dekker.com.)...

Cheng, S. T. Doxiadi. E. Vilar, R. White. A.J.P. Williams- D.J. Anion templated synthesis of Ni/Pd containing metalla-macrocycles. J. Chem. Soc. Dalton Trans. 2001.2239-2244. "... 

Scheme 6.27. Self-assembly reactions to form metalla-macrocycles 210 and 211 and solid-state structuret of 211...

Most macrocycles composed of half-sandwich complexes are positively charged and water soluble. The water solubility and stability of organometallic compounds are advantageous, and organometallic chemistry in aqueous-phase is growing rapidly [18]. The overall hydrophilicity of the metalla-cycles combined with potential inner hydrophobic interactions with guest molecules have been exploited previously. 

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