Factors controlling the structure of alkylzinc amidinates: on the role of N-substituents. Issue 9 (7th February 2023)

• Record Type: Journal Article
• Authors: Terlecki, Michał; Justyniak, Iwona; Leszczyński, Michał K.; Bernatowicz, Piotr; Lewiński, Janusz
• Is Part Of: Dalton transactions. Volume 52:Issue 9(2023)
• Page Start: 2712
• Page End: 2721
• Publication Date: 2023-02-07
• Subjects: Chemistry, Inorganic -- Periodicals; Chemistry, Physical and theoretical -- Periodicals; Chemistry, Inorganic -- Periodicals; 546.05
• DOI: 10.1039/d2dt03722j
• Languages: English
• ISSNs: 1477-9226

Abstract

Abstract : Systematic studies of model alkylzinc amidinates with a tunable secondary coordination sphere enable a more in-depth understanding of the factors controlling their structure and stability. Abstract : Despite various applications of alkylzinc complexes supported by N, N -bidentate ligands in chemistry and materials science, the corresponding organozinc amidinates still represent an insufficiently explored area. To gain a more in-depth understanding of factors controlling the structure and stability of alkylzinc amidinates, we selected benzamidinate and N, N ′-diphenylformamidinate ligands as model N, N ′-unsubstituted and N, N ′-diaryl substituted ligands, respectively, to systematically modify the secondary coordination sphere of the Zn center. A series of new alkylzinc amidinates has been synthesized and their molecular structures identified in both the solid state (single-crystal X-ray crystallography) and solution (NMR and FTIR spectroscopy). The results indicate that [RZnL] x -type amidinate moieties are essentially unstable and tend to undergo Schlenk equilibria-mediated ligand scrambling leading to more thermodynamically stable non-stoichiometric [R2 Zn3 L4 ]- and [R3 Zn4 L5 ]-type complexes. This process is significantly influenced by the secondary coordination sphere noncovalent interactions as well as the steric hindrance provided by both zinc-bounded alkyl groups and the N -substituents.