Observation of the rare chrysene excimer

Oleg Khorev,Markus Probst,Caroline D Bösch,Robert Häner

doi:10.1039/c3sc53316f

Abstract

Formation of the so far elusive chrysene excimer in solution is achieved by using DNA as a supramolecular scaffold.

Highlights

Chrysene (Fig. 1) is an alternant polycyclic aromatic hydrocarbon (PAH).[1]
Chrysene excimer fluorescence has been unambiguously observed in DNA double strands, as well as in single strands containing two neighbouring chrysenes
Chrysene excimer emission could not be detected in LB lms,[13] nor was it observed in pure single crystals.[14,15]

Summary

Introduction

Chrysene (Fig. 1) is an alternant polycyclic aromatic hydrocarbon (PAH).[1]. Compared to other PAHs such as pyrene, benzo [a]pyrene, or linear acenes, it has met rather limited interest as a substrate for biological or electronic applications or for use in the materials sciences.[2]. Birks himself to postulate that perhaps chrysene is the only PAH that cannot form an excimer.[12] Chrysene excimer emission could not be detected in LB lms,[13] nor was it observed in pure single crystals.[14,15] So far the only experimental evidence for its formation has been obtained from a high pressure study of chrysene microcrystals.[16] a possible excimer component was observed in chrysene containing vinyl copolymers.[17]. Non-nucleosidic dialkynyl PAH building blocks,[52,53] as well as nucleoside-derived, alkynylsubstituted PAHs have been introduced into DNA by several groups.[54,55,56,57,58,59] Here, we report on the formation and characterization of the chrysene excimer in single and double stranded DNA (Fig. 1)

Results and discussion

Conclusion

General procedures

Synthesis of compound 5

Oligonucleotides and duplexes