Characterization of novel TCNQ and TCNE 1:1 and 1:2 salts of the tetrakis(dimethyamino)ethylene dication, [{(CH3)(2)N}C-2-C{N(CH3)(2)}(2)](2+)

Addition of TCNQ to a solution of tetrakis(dimethylamino) ethylene in MeCN produces the salt [TDAE][TCNQ](2); the dipositive cation, [{(CH3)(2)N}C-2-C{N(CH3)(2)}(2)](2+), is nonplanar, with a dihedral angle of 63.9 degrees, while the TCNQ anions crystallize as [TCNQ](2-)(2) dimers with an interplanar separation of 3.16 Angstrom. The complex [TDAE][TCNE] was prepared in a similar manner; the [TDAE](2+) cation and [TCNE](2-) anion are nonplanar, with dihedral angles of 71.3 and 76.6 degrees, respectively. The four CN groups in the [TCNE](2-) anion each accept three C-HN hydrogen bonds. In each case, one C-N ... H angle is in the range 134-156 degrees, while the other two are near 90 degrees (81-100 degrees).