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All-Thiophene-Based Double Helix: Synthesis, Crystal Structure, Chiroptical Property and Arylation.

ABSTRACT: The all-thiophene-based double helix DH-1 was designed and prepared originally from the selective deprotonation of cyclooctatetrathiophene (tetra[3,4]thienylene, COTh) and following the Negishi coupling reaction with 3,3'-bithiophene. The X-ray crystallographic studies revealed that DH-1 has a double-helical scaffold. The arylations including tetraphenylation and tetrathienylation were efficiently employed to replace the four ?-protons of the central COTh of DH-1 with phenyl and thiophenyl groups via cross-coupling reactions. The chiral resolution of rac-DH-1 was fulfilled via chiral high-performance liquid chromatography, and the chiroptical properties were characterized by circular dichroism spectra and optical rotation. Ultraviolet-visible absorption and fluorescence behaviors of DH-1 and its arylation products were also characterized to describe the extended conjugated scaffold.

SUBMITTER: Li B

PROVIDER: S-EPMC6644213 | biostudies-literature | 2018 Nov

REPOSITORIES: biostudies-literature

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All-Thiophene-Based Double Helix: Synthesis, Crystal Structure, Chiroptical Property and Arylation.

Li Bingbing B Zhang Sheng S Li Lu L Ma Zhiying Z Li Chunli C Xu Li L Wang Hua H

ACS omega 20181127 11

The all-thiophene-based double helix DH-1 was designed and prepared originally from the selective deprotonation of cyclooctatetrathiophene (tetra[3,4]thienylene, COTh) and following the Negishi coupling reaction with 3,3'-bithiophene. The X-ray crystallographic studies revealed that DH-1 has a double-helical scaffold. The arylations including tetraphenylation and tetrathienylation were efficiently employed to replace the four α-protons of the central COTh of DH-1</ ...[more]

PMID: 31458239

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