New anionic acceptors Br2XQNHCH2SO3- [X=Br, BryCl1-y (y ≈ 0.5), and Cl; Q=1,4-benzoquinone) and their charge-transfer salts

Abstract

We have prepared new organic anionic acceptors, Br2XQNHCH 2SO3- (2: X=Br, 3: X = BryCl1-y (y ≈ 0.5), 4: X=Cl; Q=1,4-benzoquinone), that possess both an electron acceptor part (1,4-benzoquinone) and an anionic part (sulfonate). The reduction potentials of the PPh4 salts of 2, 3 and 4 are -0.45, -0.45 and -0.46 V (vs. SCE in CH3CN), respectively. The results indicate that they are weaker acceptors than chloranil (-0.13 V) and bromanil (-0.12 V). Each anionic acceptor (AA) provided two BEDT-TTF salts, β-(ET) 5(AA)2 · DCE · H2O and λ-(ET)2(AA) · CH3OH (AA=2, 3, or 4; z=2: 0.97, 3: 0.83 and 4: 0.40). The structures and transport properties of the salts are reported. © 2010 Elsevier B.V. All rights reserved.