text: Acetylacetone and related 1,3-diketones condense with primary alkyl- or arylamines resulting in replacement of the carbonyl oxygen atoms with NR groups, where R = aryl, alkyl. To prepare 1,3-diketimines from bulky amines, e.g. 2,4,6-trimethylanilines, prolonged reaction times are required.  2,6-Diisopropylaniline is a common bulky building block.
  Deprotonation of HNacNac compounds affords anionic bidentate ligands that form a variety of coordination complexes. Some derivatives with large R groups can be used to stabilize low valent main group and transition metal complexes.  Unlike the situation for the acetylacetonates, the steric properties of the coordinating atoms in NacNac ligands is adjustable by changes in the R substituent.  Attachment to a metal center is usually carried out by initial deprotonation of HNacNac with n-butyllithium; the lithium derivative is then treated with a metal chloride to eliminate lithium chloride.  In some cases, HNacNacs also serve as charge-neutral 1,3-diimine ligands.