Synthesis and electrochemistry of new tetrathiafulvalene (TTF) dendrimers: X-ray crystal structure of a tetrafunctionalised TTF core unit

A new synthetic approach to tetrathiafulvalene (TTF) dendrimers is reported. Tetrakis (4-chloromethylbenzylthio)tetrathiafulvalene 7 is a functionalised core unit which reacts with four equivalents of the thiolate ion generated from compound 16 to afford the trisdeca-TTF derivative 3. Compound 3 is a shelf-stable solid which has been characterised by elemental analysis? MALDI-TOF mass spectrometry, H-1 NMR spectroscopy and solution electrochemistry. Thin layer cyclic voltammetry studies on Fentakis-TTF and trisdeca-TTF derivatives 11 and 3 in dichloromethane solution in the presence of 2,3-dichloronaphthoquinone as an internal reference, show that all the TTF units undergo two single-electron oxidations. The single crystal X-ray structure of compound 7 is reported: the molecules have crystallographic C-i symmetry and form chair-like stacks parallel to the crystallographic y axis.