52066-87-2Relevant academic research and scientific papers
Fast oxidative cyclooligomerization towards low- and high-symmetry thiophene macrocycles
Maier, Stefan K.,Poluektov, Georgiy,Jester, Stefan-S.,M?ller, Heiko M.,H?ger, Sigurd
, p. 1379 - 1384 (2016)
Macrocycles with quaterthiophene subunits were obtained by cyclooligomerization by direct oxidative coupling of unsubstituted dithiophene moieties. The rings were closed with high selectivity by an α,β′-connection of the thiophenes as proven by NMR spectroscopy. The reaction of the precursor with terthiophene moieties yielded the symmetric α,α′-linked macrocycle in low yield together with various differently connected isomers. Blocking of the β-position of the half-rings yielded selectively the α,α′-linked macrocycle. Selected cyclothiophenes were investigated by scanning tunneling microscopy, which displayed the formation of highly ordered 2D crystalline monolayers. Heteroaromatic rings: Thiophene macrocycles with an unconventional α,α′- or α,β′-connection are readily synthesized by oxidative cyclooligomerization of the appropriate thiophenes. The actual reaction outcome strongly depends on the precursor structure (see scheme).
