The sequential lithiation mechanism for the selective deprotonation of tetra[3,4]thienylene (1) to form Li4-1 in the present of n-BuLi in THF is investigated. The specific contralateral and ipsilateral selectivities of the lithiation sites in the different steps are explored. A series of tetra-substituted 1 are obtained, viaLi4-1 with electrophiles, in good yields.

Two novel dendrimers, 16T and 20T, based on 1,1,2,2-tetra(thiophen-2-yl)ethene (4T) as a new dendron, were efficiently synthesized via carbonylation, Suzuki, and McMurry reactions. All intermediates and title compounds were fully characterized by 1H NMR, 13C NMR, and HRMS. 4T and 16T were confirmed by X-ray single crystal analyses. In addition, the absorption behaviors of two titled dendrimers are also described.

In this work, the racemate and mesomer of the thiophene-based naphthalene-cored double helicenes (1) were obtained efficiently by one-pot photocyclization of 1,1,2,2-tetrakis(dithieno[2,3-b:3′,2′-d]thiophen-2-yl)ethene in the presence of iodine in dry benzene. The structure of meso-1a was confirmed by single crystal X-ray analysis. The chiral resolution of the racemate was carried out by chiral HPLC, and the chiral properties, such as CD spectra, optical rotations, and half-life of enantiomers were characterized.

The sequential lithiation mechanism for the selective deprotonation of tetra[3,4]thienylene (1) to form Li4-1 in the present of n-BuLi in THF is investigated. The specific contralateral and ipsilateral selectivities of the lithiation sites in the different steps are explored. A series of tetra-substituted 1 are obtained, viaLi4-1 with electrophiles, in good yields.