Novel ?-Extended Thiophene-Fused Electron Acceptors for Organic Metals

Article abstract of DOI:10.1021/jo00049a027

Novel ?-extended thiophene-fused TCNQ-type and DCNQI-type acceptors have been synthesized from the corresonding quinones by reaction with Lehnert's reagent and bis(trimetylsilyl)carbodiimide (BTC), respectively.Additionally, an example of the little-known hybrid TCNQ-DCNQI-type acceptor has also been obtained.The cyclic voltammetric data of the novel acceptors reveal two different behaviours for these molecules.The TCNQ-type derivatives exhibit a two-electron single-wave reduction to the dianion, as confirmed by controlled potential coulometry analysis.The DCNQI-type derivatives display two reduction waves to the corresponding radical anion and dianion.The same behaviour is shown by the hybrid TCNQ-DCNQI derivative.The acceptor ability is related to molecular planarity, and a comparative crystallographic study involving TCNQ-type and DCNQI-type derivatives (6a, 7a, and 8a) has been performed.