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Introduction of chirality in the field of molecular conductors has received increasing interest in recent years in the frame of modulation of the crystal packing, and hence conducting properties, with the number of stereogenic centers and absolute configuration, e.g., racemic or enantiopure forms. Here, we describe the preparation by electrocrystallization of chiral radical cation salts, based on the donors methyl-ethylenedithio-tetrathiafulvalene (Me-EDT-TTF) 1 and ethyl-ethylenedithio-tetrathiafulvalene (Et-EDT-TTF) 2 containing one stereogenic center, with the perchlorate anion. Donor 1 provided the series of crystalline materials [(rac)-1]ClO4, [(S)-1]2ClO4 and [(R)-1]2ClO4, while for donor 2 only the 1:1 salts [(rac)-2]ClO4 and [(R)-2]ClO4 could be prepared as suitable single crystals for X-ray analysis. The enantiopure salts of 1 show b-type packing and metallic conductivity in the high temperature regime, with room temperature conductivity values of 5–10 S cm−1, whereas compound [(rac)-2]ClO4 is a very poor semiconductor. Tight-binding extended Hückel band structure calculations support the metallic conductivity of the enantiopure salts of 1 and suggest that small structural changes, possibly induced by thermal contraction or pressure, could lead to a pseudo-elliptic closed Fermi surface, typical for a 2D metal.

(DT-TTF)[Cu(dcdmp)(2)] (1), (DT-TTF)(2)[Cu(dcdmp)(2)] (2), and (DT-TTF)(3)[Cu(dcdmp)(2)](2) (3) are three new charge transfer salts obtained by electrocrystallization of the donor DT-TTF (dithiophene-tetrathiafulvalene) with the diamagnetic copper complex [Cu(dcdmp)(2)](-) (dcdmp = 2,3-dicyano-5,6-dimercaptopyrazine). Compounds 1 and 3 crystallize in the triclinic system and consist of out-of-registry layers of mixed stacks of donor and acceptor molecules. (DT-TTF)(2)[Cu(dcdmp)(2)] presents a structure similar to the parent spin-ladder systems with donor stacks arranged in pairs; however, a magnetic spin-ladder behavior is not observed probably due to strong interactions between pairs. Compound 3, despite the mixed nature of the stacks, displays relatively high conductivity (7 S/cm) due to a one-dimensional network of interactions between donors.