TCNE reagent

With substances that give up an electron more readily than aromatic hydrocarbons, such as potassium, nickel carbonyl, cyanide ion, or iodide ion, complete transfer of an electron occurs and the TCNE anion radical is formed (11). Potassium iodide is a particulady usefiil reagent for this purpose, and merely dissolving potassium iodide in an acetonitrile solution of TCNE causes the potassium salt of the anion radical to precipitate as bronze-colored crystals. 

Scheme 30. Reagents i, maleic anhydride, benzene, JJ, 2.5 d ii, TCNE, CHClj, 25 C, 12 h.

Thallium derivatives of the tetracyanoethylene system are of interest as reagents for the introduction of TCNE] and [TCNE] (useful in the preparation of molecular-based magnets) via a halide- abstraction... 

Cleavage of the SnSn bond can also be brought about by electron transfer reactions with reagents such as tetracyanoethylene (TCNE), tetracyanoquinodimethane, and tetra-chloroquinone for example, TCNE and MegSn2 gives the radical adduct... 

Ozonization. Since TCNE itself is stable to ozone, even at room temperatiijre, Criegee and Gunther ozonized tetramethylethylene in ethyl acetate at —70°° in the presence of 1 equivalent of the reagent in the hope that it might trap a postulaated... 

Dehydrogenation. TCNE is an effective reagent for aromatization of 1,4-di-hydrobenzenoids ... 

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