Oxygenation of RZn(N,O)-type complexes as an efficient route to zinc alkoxides not accessible via the classical alcoholysis path

Abstract

nation of zinc alkyls, 6-8 herein we describe the synthesis and Scheme 1 Representation of divergent solid-state product formation by the controlled oxygenation of alkylzinc complexes incorporating monoanionic X,Y-bidentate ligands.

Reaching Milestones in the Oxygenation Chemistry of Magnesium Alkyls: towards Intimate States of O2 Activation and the First Monomeric Well‐Defined Magnesium Alkylperoxide

“…Moreover, we have also emphasized the essential role of the coordination state of the oxygenated organoaluminum and organozinc compounds, as well as the geometric requirements of an O 2 molecule approaching the metal centre . Apart from the fundamental aspects, these systematic studies have advanced rational design of metal alkyl/air systems as radical initiators for organic reactions, stoichiometric and catalytic asymmetric epoxidation of enones and pave the way to well‐defined metal alkoxides (not accessible through the classical alcoholysis path) as potential initiators of cyclic esters polymerization as well as to a new approach for the preparation of semiconductor zinc oxide quantum dots based on organozinc/air systems …”

“…Moreover, despite the structural diversity of isolated metal alkylperoxides with non‐redox‐active centres, knowledge of their modes of further transformation still appears to be fragmentary. Our group's systematic studies on the reactivity of zinc alkyls towards O 2 have demonstrated that not only zinc alkylperoxides and alkoxides, but also zinc peroxide, hydroxide, oxo and even carboxylate species can be isolated from the controlled oxygenation of organozincs. Furthermore, we have provided compelling evidence that a variety of oxygenation products result from the decomposition of (L)ZnOOR species mediated by the O−O bond scission.…”

“…[12,20,22] Moreover,d espite the structurald iversityo fi solatedm etal alkylperoxides with nonredox-active centres, knowledge of their modes of further transformations till appears to be fragmentary. Ourgroup's systematics tudies on the reactivity of zinc alkyls towards O 2 have demonstratedt hat not only zinc alkylperoxides and alkoxides, [15,17,24,25] but also zinc peroxide, [26,27] hydroxide, [24,26,27] oxo [28,29] and even carboxylate [30] speciesc an be isolated from the controlledo xygenation of organozincs.F urthermore, we have provided compelling evidence that av ariety of oxygenation products result from the decomposition of (L)ZnOOR species mediated by the OÀOb ond scission. Recently,w ed emonstratedt hat the observed diversity of the reactiono utcomes may be ad istinguishing feature of as ingle reaction system based on dinuclear alkylzinc complexes incorporating as terically encumbered bis(b-diketiminate) ligand.…”

“…Moreover,w eh ave also emphasizedt he essential role of the coordination state of the oxygenated organoaluminum [33,34] and organozinc [5,15,16,24] compounds, as well as the geometric requirementso fa nO 2 molecule approachingt he metal centre. [33,34] Apart from the fundamental aspects, these systematic studies have advanced rational designo fm etal alkyl/airs ystemsa sr adicali nitiators for organic reactions, [35][36][37] stoichiometric [38,39] and catalytic asymmetric epoxidation of enones [11,14,40] and pave the way to welldefined metal alkoxides (not accessible through the classical alcoholysis path) as potentiali nitiators of cyclic esters polymerization [25,41] as well as to an ew approach for the preparation of semiconductor zinc oxide quantum dots based on organozinc/ air systems. [42][43][44][45][46] Notably,t he oxygenationc hemistry of magnesium alkyls has remained anu ndeveloped area of research due to difficulties to control the respective reactions ystemsr esulting from the exceptionali nstability of MgOOR species.…”

Unravelling Structural Mysteries of Simple Organozinc Alkoxides

“…In this regard, the multifaced chemistry of zinc alkoxides has a particularly long history and can be traced back to Frankland's pioneering studies [3] . This interest in zinc alkoxides has been driven by several perspectives including synthetic methodology, [4–9] molecular structure, [4–20] reactivity, [9–11, 16, 18, 20–29] potential applications of zinc alkoxides both in catalytic reactions, [21, 23, 24, 30, 31] and more recently in materials science as predesigned precursors of zinc oxide nanostructures [15, 22, 26–29, 32–34] . Over time, a wide variety of their structural motifs (see below) and diverse transformations in the solid state and solution emerged.…”