Tetrakis(dimethylamino)ethylene (TDAE) is an organic compound with the formula , It is a colorless liquid. It is classified as an enamine. Primary and secondary enamines tend to isomerize, but tertiary enamines are kinetically stable. One unusual feature of TDAE is that it is a tetra-enamine. The pi-donating tendency of the amine groups strongly enhances the basicity of the molecule, which does exhibit properties of a typical alkene.
Reactions TDAE reacts with oxygen in a chemiluminescent reaction to give tetramethylurea. The initial intermediate is (2+2) adduct, a 1,2-dioxetane. This species decomposes to electronically excited tetramethylurea. This returns to the ground state is accompanied by emission of green light with a maximum at 515 nm.
TDAE is an electron donor with E = 1.06 V vs Fc+/0.
TDAE has been examined as a reductant in coupling reactions.
As one of many of examples of its redox behavior forms a charge-transfer salt with buckminsterfullerene: C2(N(CH3)2)4 + C60 → [C2(N(CH3)2)4+][C60−]
Oxidation affords a dication.
Structure Crystallographic analysis show that TDAE is a highly distorted alkene, the dihedral angle for the two N2C ends is 28°. The C=C distance is alkene-like, 135 pm. The nearly isostructural tetraisopropylethylene also has a C=C distance of 135 pm, but its C6 core is planar. In contrast, [TDAE]2+ is an alkane with multi-C-N bonds.
Synthesis It is available by pyrolysis of tris(dimethylamino)methane or from chlorotrifluoroethene and dimethylamine.
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