Trapping of AlMe₃with the Oxygen Atom of the Zr₃(μ₃-O) Unit

Abstract

We report for the first time the direct complexation of AlMe 3 by a Zr 3 (µ 3 -O) core. The precursor [Zr 4 (µ 4 -O)(µ-OMe) 6 Cl 8 (thf) 4 ] (1) was obtained in the direct reaction of ZrCl 4 with methanol. When 1 was allowed to react with AlMe 3 , [Zr 3 Al(µ 4 -O)(µ-OMe) 6 Cl 6 -(Me)(thf) 3 ] (2) was isolated. An analogous trend was observed in the compound [Zr 4 Al 2 (µ 4 -O) 2 (OEt) 12 Cl 6 ] (3), which was obtained in the direct reaction of ZrCl 4 with Zr(OEt) 4 and Al in thf/EtOH.(1) (a) Bochmann, M.

Syntheses and Molecular Structure of [Mg2(OR)4(AlMe3)2] and [ZrCl3(OR)2(AlMe2)] (OR = 1-methoxy-2-propoxide)

“…6 In summary, we have demonstrated that the magnesium dicubane-like species [Mg 4 (OR) 8 ] (1) can graft AlMe 3 to form [Mg 2 (OR) 4 (AlMe 3 ) 2 ] (2). This is reminiscent of the hydrolysis of AlMe 3 , which produces the methylalumoxane (MAO) polymerization cocatalyst, which is believed to contain both AlMe 3 and AlMe x (O) units. 7 Moreover, compounds 2 react further with ZrCl 4 and [ZrCl 3 (OR) 2 (AlMe 2 )] (3) is formed.…”

“…1,2 Our research has focused on determining the role of each of the components of the catalyst, which is still extensively used in the polyolefin industry. 3 Very recently we reported the coordination of AlMe 3 to the oxygen atom of the Zr 3 (µ 3 -O) core present in the product of the reaction of ZrCl 4 with MeOH, [Zr 3 -Al(µ 4 -O)(µ-OMe) 6 Cl 6 (Me)(thf) 3 ]. 4a To provide further information on compounds and reaction steps that lead to the formation of the active catalyst species, we report here the complexation of AlMe 3 by the alkoxide oxygen atoms of Mg 2 (OR) 4 and Zr(OR) 2 units.…”

A Family of Group 4 Metal Alkoxo Complexes with an M3(μ3‐O) Core Relevant to Ziegler–Natta Catalyst Intermediates

“…Further investigation of 3 ± 6 showed that even with very strong alkylating agents the structure of the M 3 triangle (including the terminal chlorine atoms) remained untouched, proving the high stability of the trinuclear core. [28] This stability prevents any metallic center in such a precatalyst from being activated (for example, by removal of a chlorine atom) and became a polymerization center. It has also been shown that AlMe 3 reacts with [Mg(thffo) 2 ] to form a complex similar to 3 ± 6, namely tetranuclear bimetallic [Al 3 Mg(m 3 -O) (thffo) 3 (Me) 6 ], which has a tetranuclear Al 3 (m 3 -O) core [29] capped with the magnesium moiety.…”

Assembly of an Oxo–Zirconium(IV) Cluster in a Protein Cleft

“…Low‐molecular‐weight alkoxide and aryloxide ligands have been used in the synthesis of small organically functionalized oxo–Zr IV clusters 1. 14–17 The experiments described herein show that oxo–trizirconium clusters anchored by a dityrosyl (diphenolate) motif readily assemble in the hinged cleft of a protein, bacterial transferrin. The provision of a protein coat for a polyoxometalate cluster could have several advantages.…”