Soluble Alumotitanosilicates and Their Zirconium and Hafnium Analogues

Abstract

The synthesis of molecular heterometallic alumosilicates in good yields has been achieved by reaction between LAl(OH·thf)(μ‐O)Si(OH)(OtBu)2 (1, L = [HC{C(Me)N(Ar)}2]–, Ar = 2,6‐iPr2C6H3) and group 4 amides. These reactions lead to inorganic cycles (type I) and spirocycles (type II) containing six‐membered rings with unprecedented inorganic cores (O–Al–O–Si–O)nM (n = 1, 2; M = Ti, Zr and Hf). Noteworthy, for the heavier metals, Zr and Hf, higher steric bulk in the alkyl substituent of the amide moiety is required to obtain type I compounds. The solid‐state structures for all compounds were determined and reveal a tetrahedral environment for all metal atoms, dihedral angles close to 90° for spirocyclic compounds, and isomorphous structures for the Zr and Hf derivatives.

Hydrolysis of organometallic and metal–amide precursors: synthesis routes to oxo-bridged heterometallic complexes, metal-oxo clusters and metal oxide nanoparticles

“…11). While this is generally a successful method to access mixed-metal-oxo species, the choice of the metal, nature of the organo-or amide group, and the reaction stoichiometry influences whether a bimetallic 147 So far, this synthetic strategy appears to be somewhat limited in its use for preparing complexes with more than three metal centres from a monohydroxide precursor.…”

Inorganic heterocycles based on alumosilicate-sulfide ligand

“…Nonetheless, due to the different shape of the crystals for 5 and 6, both molecular structures could be determined by hand picking the appropriate crystals. The HR-MS spectra for these crystals shows peaks at m/z 805.2902 belonging to the ion [M+K] + (5) or at m/z 867.2999 representing the [M À GaMe 3 À Me] + fragment of 6. The 1 H NMR spectrum of gently dried crystals of 6 shows the presence of minor amounts of at least four other compounds.…”

“…In our search for unusual inorganic heterocycles, we became interested in the possibility of deprotonating both groups by the same metal atom and forming covalent S-Al-O-Si-O-M rings. This should be possible as the oxygen homologue [LAl(OH)(l-O)Si(OH)(O t Bu) 2 ] can be transformed with group 4 metal amides into the corresponding cyclic or spirocyclic compounds [5]. Moreover, the Al-SH group is more reactive than the Al-OH moiety and the Al-S bond length in 1 is with 2.22 Å significantly longer than the Al-O distance in [LAl(OH) (l-O) increases the possibility to form the desired six-membered ring.…”

Alkali Metallosilicates: Synthesis, Structure and Evaluation in the ROP of ϵ‐Caprolactone

“…The molar mass of the tetrameric 1 is 1,081.48 g mol À 1 and the 1 H DOSY NMR spectrum of 1 was acquired using two internal standards A: [52] and B: [Si-(O t Bu) 2 (μ-O)] 3 [53] with M r = 570.94 g mol À 1 . The D were 7.66 × 10 À 10 for A (average of 29 values) and 1.00 × 10 À 9 for B, respectively.…”