A Straightforward Synthesis of N‐Functionalized β‐Diimines

Reaction of Schwartz’s reagent [Cp2ZrHCl]n (1) (one or two equivalents) with gem‐dinitrile compounds of the type X(CN)2 [X = CMe2, CBenz2, P(NiPr2)2] gives the corresponding mono‐ and di‐N‐zirconated imino complexes selectively. Substitution reactions of the zirconocene metal fragment with electrophiles such as, for example, chlorophosphanes of the type R2PCl, acid chlorides RC(O)Cl or the iminium salt [CH2NMe2]Cl allowed the preparation of a large variety of stable N‐functionalized mono‐ and β‐diimine derivatives. The nature of the X group is of particular importance for the success of the substitution reaction step. The X‐ray crystal structures obtained for the N‐functionalized gem‐aldimino‐nitrile compounds 9, 10b, the N‐phosphorylated β‐diimine 32, and the gem‐formyl nitrile derivative 12b are presented. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)