Vinylogs of tetrathiafulvalene (TTF) bearing four 1,4-dithiafulven-6-yl substituents : Novel highly extended and sulfur-rich π-donors
摘要:
The title compounds 1 were synthesized from the mono-diEt-acetal of acetylenedicarbaldehyde and 2-thioxo-1,3-dithioles through three key steps: cycloaddition, dimerization-desulphurization of the resulting thials, and after deketalization, fourfold Wittig olefination of the tetraformyl TTF-vinylogs 4 with the P-ylids Walpha-gamma bearing the 1,3-dithiol-2-ylidene moiety. Cyclic voltammetry shows that these compounds are very strong pi-donors and good precursors of conducting cation-radical salts.
Cycloaddition of 3-thioxo-12-dithioles onto acetylenedicarbaldehyde and its mono-diethylacetal : Ready access to intermediates in the tetrathiafulvalene (TTF) series
摘要:
The 4,5-diformyl-1,3-dithiol-2-ylidene ethanals and ethanones 4 are prepared by a three-step sequence from acetylenedicarbaldehyde mono-diEt-acetal and 3-thioxo-1,2-dithioles. Their X-ray diffraction structure, H-1 nmr and IR properties, reveal a delta-cis conformation in the solid state and in solution, due to strong S...O 1,5-internal bonding interactions.