One-pot synthesis of highly emissive dipyridinium dihydrohelicenes
Abstract
Condensation of a pyridyl-2-carbaldehyde derivative with 2-(bromoethyl)amine hydrobromide gave tetracyclic pyrido[1,2-a]pyrido[1',2':3,4]imidazo-[2,1-c]-6,7-dihydropyrazinium dications in excellent yields. Crystal structures and NOE data demonstrated the helical character of the dications, the dihedral angles between the two pyrido groups ranging from 28-45°. An intermediate in the synthesis was also characterized. A much brighter emission compared to literature helicenes has been found, with quantum yields as high as 60 % in the range of λ=460-600 nm. Preliminary cytotoxicity studies against HT-29 cancer cells demonstrated moderate-to-good activity, with IC50 values 12-30× that of cisplatin.
Citation
Santoro , A , Lord , R M , Loughrey , J J , McGowan , P C , Halcrow , M A , Henwood , A F , Thomson , C & Zysman-Colman , E 2015 , ' One-pot synthesis of highly emissive dipyridinium dihydrohelicenes ' , Chemistry - A European Journal , vol. 21 , no. 19 , pp. 7035-7038 . https://doi.org/10.1002/chem.201406255
Publication
Chemistry - A European Journal
Status
Peer reviewed
ISSN
0947-6539Type
Journal article
Description
This work was funded by the EPSRC (EP/I014039/1). E.Z.C. acknowledges the University of St. Andrews for funding. C.T. thanks MUSA for financial support.Collections
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