Gram-Scale Synthesis and Highly Regioselective Bromination of 1,1,9,9-Tetramethyl[9](2,11)teropyrenophane

Kiran Sagar Unikela; Tracey L Roemmele; Václav Houska; Kaitlin E McGrath; David M Tobin; Louise N Dawe; René T Boeré; Graham J Bodwell

doi:10.1002/anie.201713067

Gram-Scale Synthesis and Highly Regioselective Bromination of 1,1,9,9-Tetramethyl[9](2,11)teropyrenophane

Angew Chem Int Ed Engl. 2018 Feb 5;57(6):1707-1711. doi: 10.1002/anie.201713067. Epub 2018 Jan 16.

Authors

Kiran Sagar Unikela¹, Tracey L Roemmele², Václav Houska³, Kaitlin E McGrath¹, David M Tobin², Louise N Dawe⁴, René T Boeré², Graham J Bodwell¹

Affiliations

¹ Department of Chemistry, Memorial University of Newfoundland, St. John's, NL, A1B 3X7, Canada.
² Department of Chemistry, University of Lethbridge, 4401 University Drive, Lethbridge, AB, T1K 3M4, Canada.
³ Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Flemingovo nám. 2, 166 10, Prague 6, Czech Republic.
⁴ Department of Chemistry and Biochemistry, Wilfrid Laurier University, 75 University Avenue W., Waterloo, ON, N2L 3C5, Canada.

PMID: 29272562
DOI: 10.1002/anie.201713067

Abstract

An improved synthetic pathway to the nanobelt-like 1,1,9,9-tetramethyl[9](2,11)teropyrenophane has been developed, and enables the synthesis of gram quantities of material. Key innovations are the development of a sequential chlorination/Friedel-Crafts alkylation reaction, a sequential iodination/Wurtz coupling reaction, and a room-temperature teropyrene-forming reaction. The teropyrenophane was found to form a very stable radical cation and undergo a completely regioselective fourfold bromination reaction.

Keywords: EPR spectroscopy; aromaticity; bromination; cyclophanes; structure elucidation.

Publication types

Research Support, Non-U.S. Gov't