Rotaxane catalytically active

Aucagne V, Bema J, Crowley JD, Goldup SM, Hanni KD, Leigh DA, Lusby PJ, Ronaldson VE, Slawin AMZ, Viterisi A, Walker DB (2007) Catalytic active-metal template synthesis of [2]rotaxanes, [3]rotaxanes, and molecular shuttles, and some observations on the mechanism of the Cu(I)-catalyzed azide-alkyne 1, 3-cycloaddition. J Am Chem Soc 129 11950-11963... 

Catalytically Active Rotaxanes as Processive Enzyme Mimics... 

Apart form a great number of chiral NHC carbenes that have been used as ligands in enantioselective transition-metal catalysis (Gade and Bellemin-Laponnanz 2007), some less usual heterazolium salts have been tested in organocatalytic transformations. A planar-chiral thia-zolium salt (Pesch et al. 2004) and a rotaxane-derived precatalyst were reported (Tachibana et al. 2004), as well as catalytically active peptides containing an unnatural thiazolium-substituted alanine amino acid (Fig. 3 Mennen et al. 2005a,b). 

Thordarson, P., Nolte, R. J. M. and Rowan, A. E., Mimicking the motion of life catalytically active rotaxanes as processive enzyme mimics, Aust.. Chem., 2004, 57, 323-327. 

In a somewhat related work, Nolte, Rowan et al. [13] described in 2003 a rotaxane complex that mimics the ability of processive enzymes to catalyze multiple rounds of reaction while the polymer substrate stays bound. The catalyst, which consists of a substrate-binding cavity incorporating a manganese] 111) porphyrin complex acting as the catalytic center, can oxidize alkenes complexed within the toroid cavity, provided a ligand has been attached to the outer face of the toroid to both activate the porphyrin complex and prevent it from being able to oxidize alkenes outside the cavity. 

Chemical templation has been widely employed for the synthesis of mechanically interlocked strucmres. Some of these interlocked systems have potential in future chemical sensor design. Leigh and coworkers prepared many [2]rotaxanes via an active-metal template synthesis. For example, a [2]rotaxane R14 synthesized via a catalytic... 

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