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Synthesis and photophysical investigation of squaraine rotaxanes by "clicked capping".

ABSTRACT: Pseudorotaxane complexes of squaraine dyes and tetralactam macrocycles are converted into permanently interlocked rotaxane structures using copper-catalyzed and copper-free cycloaddition reactions with bulky stopper groups. The photophysical properties of the encapsulated squaraine depend on the structure of the macrocycle. In one case, squaraine rotaxanes are produced in near-quantitative yields and with intense near-IR fluorescence. In another case, squaraine fluorescence is greatly diminished upon macrocyclic encapsulation but the signal can be restored by dye displacement with anions.

SUBMITTER: Gassensmith JJ

PROVIDER: S-EPMC2848988 | biostudies-literature | 2008 Aug

REPOSITORIES: biostudies-literature

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Synthesis and photophysical investigation of squaraine rotaxanes by "clicked capping".

Gassensmith Jeremiah J JJ Barr Lorna L Baumes Jeffrey M JM Paek Agelina A Nguyen Anh A Smith Bradley D BD

Organic letters 20080627 15

Pseudorotaxane complexes of squaraine dyes and tetralactam macrocycles are converted into permanently interlocked rotaxane structures using copper-catalyzed and copper-free cycloaddition reactions with bulky stopper groups. The photophysical properties of the encapsulated squaraine depend on the structure of the macrocycle. In one case, squaraine rotaxanes are produced in near-quantitative yields and with intense near-IR fluorescence. In another case, squaraine fluorescence is greatly diminished ...[more]

PMID: 18582079

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