Thallium amides bonding

Metal-Nitrogen Bond Lengths and Torsion Angles between the Metal and Nitrogen Coordination Planes for Three-Coordinate Aluminum, Gallium, Indium, and Thallium Amides... 

Although one-electron oxidation of arenes by thallium trifluoroacetate presumably does not proceed via formation of a discrete aiylthallium bond, some examples involving oxidative cyclization mediated by thallium trifluoroacetate will be considered here. Schwartz and Hudec employed thallium trifluoroacetate to effect an intramolecular cyclization of the amide (41) to give a key intermediate (42) in their projected synthesis of lycorine alkaloids (Scheme 16). Interestingly, when the bromine was replaced by a hyctogen the yield was poorer. 

The metal-oxygen products have exceptional thermodynamic stability, in part as a result of 0-M n-bonding. For amides of thallium (Me2TlNMc2/S02 or SOs) , silicon [MeaSiNRR /SOa or (MesSijaN/SOs], or tin (Me3SnNMc2/S02), adducts have been isolated . Examples of SeOa insertion into an Si-N bond are known. ... 

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