Synthesis and Characterization of Organoaluminum Complexes Containing Bi- or Tridentate-Substituted Pyrrole Ligands

Reactions of AlCl3 with 1 equiv of Li{C4H2N(CH2NMe2)2-2,5} or 2 equiv of Li{C4H3N(CH2NMe2)-2} in diethyl ether at −78 °C afforded AlCl2{C4H2N(CH2NMe2)2-2,5} (1) and AlCl{C4H3N(CH2NMe2)-2} (2), respectively. Alkylation of 1 with MeLi in diethyl ether generates the aluminum dimethyl complex 3. Compound 2 is thermally unstable and was converted to uncharacterized product in CHCl3 within 2 days at 80 °C. Compounds 1, 2, and 3 were characterized by NMR spectroscopy and X-ray structure determination