New anionic acceptors Br 2XQNHCH 2SO 3− [X=Br, Br yCl 1−y ( y≈0.5), and Cl; Q=1,4-benzoquinone) and their charge-transfer salts

Abstract

We have prepared new organic anionic acceptors, Br 2XQNHCH 2SO 3 − ( 2: X=Br, 3: X=Br y Cl 1− 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 PPh 4 salts of 2, 3 and 4 are −0.45, −0.45 and −0.46 V (vs. SCE in CH 3CN), 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· zH 2O and λ-(ET) 2(AA)·CH 3OH (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.