Efficient templated synthesis of donor-acceptor rotaxanes using click chemistry

William R Dichtel; Ognjen S Miljanić; Jason M Spruell; James R Heath; J Fraser Stoddart

doi:10.1021/ja063127i

Efficient templated synthesis of donor-acceptor rotaxanes using click chemistry

J Am Chem Soc. 2006 Aug 16;128(32):10388-90. doi: 10.1021/ja063127i.

Authors

William R Dichtel¹, Ognjen S Miljanić, Jason M Spruell, James R Heath, J Fraser Stoddart

Affiliation

¹ California NanoSystems Institute and Department of Chemistry and Biochemistry, University of California, Los Angeles, 405 Hilgard Avenue, Los Angeles, California 90095, USA.

PMID: 16895403
DOI: 10.1021/ja063127i

Abstract

The mild reaction conditions, remarkable functional group compatibility, and complete regioselectivity of the Cu-catalyzed Huisgen 1,3-dipolar cycloaddition ("click chemistry") between organic azides and terminal alkynes have led to a threading-followed-by-stoppering approach to the synthesis of donor-acceptor rotaxanes incorporating cyclobis(paraquat-p-phenylene) (CBPQT4+) as the pi-accepting ring component. Rotaxane formation is initiated by reacting azide-functionalized pseudorotaxanes containing pi-donating 1,5-dioxynaphthalene (DNP) recognition units with appropriate alkyne-functionalized stoppers. The high yields obtained in this efficient, kinetically controlled post-assembly covalent modification, as well as the excellent convergence of the synthetic protocol, are demonstrated by the preparation of [2]-, [3]-, and [4]rotaxanes containing multiple DNP/CBPQT4+ donor-acceptor recognition motifs.