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Updated: Feb 16, 2026

Preparation of Carbon Nanosheets at Room Temperature
Published on: March 8, 2016
Gram-Scale Synthesis and Highly Regioselective Bromination of 1,1,9,9-Tetramethyl[9](2,11)teropyrenophane
Kiran Sagar Unikela1, Tracey L Roemmele2, Václav Houska3
1Department of Chemistry, Memorial University of Newfoundland, St. John's, NL, A1B 3X7, Canada.
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.
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