Tmeda-Nickel-Komplexe: III. ( N,N,N′, N′-Tetramethylethylendiamin)-(dimethyl)nickel(II)

Abstract

(tmeda)Ni(acac) 2 reacts with the main group metal compounds (tmeda)Mg-(CH 3) 2, (tmeda)&[;Al(CH 3) 3&]; 2, and (C 2H 5O)Al(CH 3) 2 at 0°C to give (tmeda)Ni-(CH 3) 2 ( 1), which can be isolated as fine yellow crystals in 50–80% yield. Complex 1, which is the simplest dialkyl nickel(II) compound with a “hard” donor ligand, is surprisingly stable and decomposes only at 79°C. 1 is converted by bipy to (bipy)Ni(CH 3) 2 and by Me 2PC 2H 4PMe 2 to (Me 2PC 2H 4PMe 2)Ni(CH 3) 2. Upon reaction of 1 with strong π-acceptor molecules (acrylic acid methylester, methyl vinyl ketone, acrylonitrile, tetracyanoethene, tetrafluoroethene, maleic anhydride) reductive elimination of the methyl groups takes place to give the complexes (tmeda)Ni(π-ligand) n ( n = 1, 2) and ethane.