The whole molecule of the title compound, C22H28N2, (I), is generated by inversion symmetry. The molecule is rather similar to that of 2,3-bis[(2-tert-butylphenyl)imino]butane, (II), a diimine ligand comprising similar structural features [Ferreiraet al.(2006).Acta Cryst.E62, o4282–o4284]. Both ligands crystallize with the –N=C(R)—C(R)=N– group around an inversion centre, in atransconfiguration. Comparing the two structures, it may be noted that the independent planar groups in both molecules [the central link, –N=C(R)—C(R)=N–, and the terminal aromatic ring] subtend an angle of 69.6 (1)° in (II) and 49.4 (2)° in (I). Ferreira and co-workers proposed that such angle deviation may be ascribed to the presence of two non-classical intramolecular hydrogen bonds and steric factors. In fact, in (I), similar non-classical hydrogen bonds are observed, and the larger angular deviation in (II) may be assigned to the presence of methyl groups in the diimino fragment, which can cause steric hindrance due to the presence of bulkytert-butyl substituents in the aromatic rings. The C=N bond lengths are similar in both compounds and agree with comonly accepted values.
A Chiral Naphthyridine Diimine Ligand Enables Nickel‐Catalyzed Asymmetric Alkylidenecyclopropanations
