Highly symmetrical chromium(II) bisdiketiminate complexes

Reaction of the lithium salts of N,N′-dialkyl-2-amino-4-imino-pent-2-enes, nacnacRLi(THF) (R = CH2Ph, Cy, nPr, iBu or S–CH(Me)Ph), with half an equivalent of CrCl2(THF)x yielded the homoleptic complexes (nacnacR)2Cr. All complexes were characterized by X-ray diffraction studies and displayed a highly symmetric, square-planar coordination around the chromium center with strong boat-like distortions of the diketiminate ligands. Reaction of nacnacRLi(THF) (R = CH2Ph, Cy) with one equivalent of CrCl2(THF)x afforded the dimeric complexes {nacnacRCr(μ-Cl)}2.

Despite the presence of bulky N-alkyl substituents, chromium(II) bis(diketiminate) complexes adopt a perfectly planar coordination geometry around the chromium center.Figure optionsDownload as PowerPoint slide