Reactions of (dpp-BIAN)Mg(thf)3 complex (dpp-BIAN is 1,2-bis{(2,6-diisopropylphenyl)imino}acenaphthene) with halogen-containing reagents

Abstract

The reactions of the acenaphthenediimine complex (dpp-BIAN)Mg(thf)3 (1) (dpp-BIAN is 1,2-bis{ (2,6-diisopropylphenyl)imino}acenaphthene) with various chlorine-, bromine-, and iodine-containing reagents afforded the unsymmetrical compounds [(dpp-BIAN)MgCl(thf)]2 (6), [(dpp-BIAN)MgBr(thf)]2 (7), and (dpp-BIAN)MgI(DME) (8). The reaction of complex 1 with Me3SiCl in THF is accompanied by the cleavage of the THF molecule to form [{dpp-BIAN(CH2)4OSiMe3}MgCl]2 (9), in which the trimethylsilanyloxybutyl group is bound to one of the carbon atoms of the diimine fragment. The reaction of complex 1 with Me2NCH2CH2Cl in THF produces the [dpp-BIAN(H)(CH2)2NMe2] compound (10) containing no magnesium. Paramagnetic complexes 6–8 were characterized by ESR spectroscopy. Diamagnetic compounds 9 and 10 were studied by 1H and 13C NMR spectroscopy. The molecular structures of complexes 6–10 were established by X-ray diffraction analysis. In the crystalline state, compounds 6, 7, and 9 exist as halogen-bridged dimers. In all magnesium derivatives, BIAN serves as a chelate ligand.