Synthesis 2015; 47(22): 3479-3488
DOI: 10.1055/s-0034-1381136
paper
© Georg Thieme Verlag Stuttgart · New York

Synthesis of Helquats Based on Phenanthridinium Units: Four-Step Procedure to Novel Extended Helical Dications

Manoj R. Sonawane
a   Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i., Flemingovo n. 2, 166 10 Prague 6, Czech Republic   Email: teply@uochb.cas.cz
,
Jan Vávra
a   Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i., Flemingovo n. 2, 166 10 Prague 6, Czech Republic   Email: teply@uochb.cas.cz
,
David Šaman
a   Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i., Flemingovo n. 2, 166 10 Prague 6, Czech Republic   Email: teply@uochb.cas.cz
,
Ivana Císařová
b   Department of Inorganic Chemistry, Faculty of Science, Charles University in Prague, Hlavova 2030/8, 128 43 Prague 2, Czech Republic
,
Filip Teplý*
a   Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i., Flemingovo n. 2, 166 10 Prague 6, Czech Republic   Email: teply@uochb.cas.cz
› Author Affiliations
Further Information

Publication History

Received: 27 March 2015

Accepted after revision: 29 May 2015

Publication Date:
10 August 2015 (online)


Abstract

Three novel helical dications (helquats) containing phenanthridinium units have been synthesized from 6-(pyridin-2-ylethyn­yl)phenanthridine as a common precursor prepared by Sonogashira coupling of phenanthridin-6-yl triflate with 2-ethynylpyridine. Bisquaternization of the common precursor followed by rhodium-catalyzed [2+2+2] cycloisomerization led to the title helical dicationic scaffolds. The connectivity and spatial arrangement of the three target helquats were unambiguously established by X-ray crystal structure analysis.

Supporting Information