Synthesis, Properties, and Two‐Dimensional Adsorption Characteristics of [6]Hexahelicene‐7‐carboxylic acid. Issue 41 (24th August 2016)

• Record Type: Journal Article
• Authors: van der Meijden, Maarten W.; Balandina, Tatyana; Ivasenko, Oleksandr; De Feyter, Steven; Wurst, Klaus; Kellogg, Richard M.
• Is Part Of: Chemistry. Volume 22:Issue 41(2016)
• Page Start: 14633
• Page End: 14639
• Publication Date: 2016-08-24
• Subjects: acid functionalization -- cross-coupling -- helicene -- metal catalyzed cyclizations -- scanning tunneling microscopy; Chemistry -- Periodicals; 540
• DOI: 10.1002/chem.201603058
• Languages: English
• ISSNs: 0947-6539

Abstract

Abstract: A convergent synthesis of racemic [6]hexahelicene‐7‐carboxylic acid by cross‐coupling of a bicyclic and a tricyclic component is described. A metal‐catalyzed ring‐closure is also a fundamental component of the synthetic approach. Scanning tunneling microscopy (STM) measurements of the racemate self‐assembled on Au(111) at liquid–solid interface revealed the formation of ordered racemic 2D crystals. Abstract : A winding road : A synthesis of 7‐carboxyhexahelicene1 has been developed using a convergent cross‐coupling synthesis that provides the 7‐methyl derivative in good yield. The methyl group proved to be remarkably recalcitrant to oxidation to the carboxylic acid of1 . Self‐assembly of1 from the liquid on solid Au(111) provided monolayers of well‐ordered racemic two‐dimensional crystals.