Zinc Complexes with the Chelating Amido‐Imino Ligand [1‐n‐Butyl‐2‐(2,6‐diisopropylphenyl)iminoacenaphthen‐1‐yl]‐2,6‐diisopropylphenylamide (L): Synthesis, Molecular Structure and Reactivity of [(L)­ZnCl]2, (L)Zn‐nBu and (L)ZnN(SiMe3)2

Abstract

AbstractDimeric [(L)ZnCl]2 (4) {L = [1‐n‐butyl‐2‐(2,6‐diisopropylphenyl)iminoacenaphthen‐1‐yl]‐2,6‐diisopropylphenylamide} was prepared by treatment of the lithium salt of the ligand (LLi) with equimolar amounts of anhydrous ZnCl2. Treatment of 4 with KN(SiMe3)2 affords the bis(trimethylsilyl)amido compound (L)ZnN(SiMe3)2 (5). The alkylzinc complex (L)Zn‐nBu (6) is the product of the reaction between the adduct LLi·nBuLi (3) and ZnCl2. Compounds 4–6 were characterized by 1H NMR and IR spectroscopy. The molecular structures of 4 and 6 were determined by single‐crystal X‐ray analysis. In the solid state, the molecules of 4 exist as centrosymmetric, heterochiral dimers bridged by chlorine atoms, while compound 6 consists of monomeric molecules with three‐coordinate zinc atoms. The reactions of 6 with tert‐butanol, adamanthanol, 2,5‐di‐tert‐butylaniline and diphenylacetonitrile do not proceed with alkane elimination but with protonation of the ligand affording the amino‐imine LH (7). (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)