2-alkyloxy substituted tetracyanoallyl anions (RO-TCA(-), R = Me, Et, Pr, Bu) were examined in the formation of the radical cation salts of organic donor molecules systematically. 14 kinds of salts have been obtained so far. Among them, (BEDO-TTF)(2)(EtO-TCA)(H2O)(0.75) Showed weak metallic temperature dependence of the conductivity down to ca. 180 K (sigma(rt) = 30 S cm(-1)). The crystal structure analyses of (BEDT-TTF)(2)(PrO-TCA) (needle form) and (TTT)(MeO-TCA) revealed the layered structure in both cases. The two C(CN)(2) groups in an anion are twisted to each other in either salts. The structures of the anion layers showed the existence of various packing patterns for this anion series.