Magic ring catenation by olefin metathesis.

Org Lett

The Arnold and Mabel Beckman Laboratory of Chemical Synthesis, California Institute of Technology, Pasadena, California 91125, USA.

Published: May 2005

[reaction: see text]. Olefin metathesis has been employed in the efficient syntheses of a [2]catenane with the templation being provided by the recognition between a secondary ammonium ion and a crown ether. In one approach, a crown ether precursor has been clipped around an NH2+ center situated in a macrocyclic ring, yielding the mechanically interlocked compound. In the other approach, the reversible nature of olefin metathesis allows for a magic ring synthesis to occur wherein two free macrocycles can be employed as the stationary materials, leading to the formation of the same [2]catenane.

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http://dx.doi.org/10.1021/ol050463fDOI Listing

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