Synthesis of thiophenohelicenes and their physico-chemical properties
- Resource Type
- Authors
- Palata, Ondřej
- Source
- Subject
- Language
- English
The objective of this Thesis was to prepare thiophenohelicenes by [2+2+2] cyclotrimerization of aromatic triynes, namely dithiopheno[5]helicene, dithiopheno[6]helicene and trithiopheno[6]helicene. The Theoretical part illustrates which heteroatoms can be embedded into helicene backbone and provides few representative syntheses of such heterohelicenes along with some examples of their utilization. The Results and discussion part and Experimental part deal with the synthesis of dithiopheno[5]helicene, dithiopheno[6]helicene and (dihydro)-trithiopheno[6]helicene from commercially available compounds by the [2+2+2] cyclotrimerization of corresponding aromatic triynes as the key step in the synthesis. The UV/Vis and fluorescence spectral analyses and electrochemical measurements of the dithiopheno[5]helicene and dithiopheno[6]helicene were performed. The enantiomers of configurationally stable dithiopheno[6]helicene were separated and CD spectra as well as optical rotation of each enantiomer were measured. A barrier of racemization for dithiopheno[6]helicene was also determined.