Synthesis and Structures of ansa‐Titanocene Complexes with Diatomic Bridging Units for Overall Water Splitting. Issue 20 (27th March 2013)

• Record Type: Journal Article
• Authors: Kessler, Monty; Hansen, Sven; Godemann, Christian; Spannenberg, Anke; Beweries, Torsten
• Is Part Of: Chemistry. Volume 19:Issue 20(2013)
• Page Start: 6350
• Page End: 6357
• Publication Date: 2013-03-27
• Subjects: Chemistry -- Periodicals; 540
• DOI: 10.1002/chem.201300223
• Languages: English
• ISSNs: 0947-6539

Abstract

<abstract abstract-type="main" xml:lang="en"> <title>Abstract</title> <p>The synthesis of a series of <italic>ansa</italic>‐titanocene dichlorides [Cp′<sub>2</sub>TiCl<sub>2</sub>] (Cp′=bridged η<sup>5</sup>‐tetramethylcyclopentadienyl) and the corresponding titanocene bis(trimethylsilyl)acetylene complexes [Cp′<sub>2</sub>Ti(η<sup>2</sup>‐Me<sub>3</sub>SiC<sub>2</sub>SiMe<sub>3</sub>)] is described. The ethanediyl‐bridged complexes [C<sub>2</sub>H<sub>4</sub>(C<sub>5</sub>Me<sub>4</sub>)<sub>2</sub>TiCl<sub>2</sub>] (<bold>2</bold>‐Cl<sub>2</sub>) and [C<sub>2</sub>H<sub>4</sub>(C<sub>5</sub>Me<sub>4</sub>)<sub>2</sub>Ti(η<sup>2</sup>‐Me<sub>3</sub>SiC<sub>2</sub>SiMe<sub>3</sub>)] (<bold>2‐</bold>btmsa; btmsa=η<sup>2</sup>‐Me<sub>3</sub>SiC<sub>2</sub>SiMe<sub>3</sub>) can be obtained from the hitherto unknown calcocenophane complex [C<sub>2</sub>H<sub>4</sub>(C<sub>5</sub>Me<sub>4</sub>)<sub>2</sub>Ca(THF)<sub>2</sub>] (<bold>1</bold>). Furthermore, a heterodiatomic bridging unit containing both, a dimethylsilyl and a methylene group was introduced to yield the <italic>ansa</italic>‐titanocene dichloride [Me<sub>2</sub>SiCH<sub>2</sub>(C<sub>5</sub>Me<sub>4</sub>)<sub>2</sub>TiCl<sub>2</sub>] (<bold>3</bold>‐Cl<sub>2</sub>) and the bis(trimethylsilyl)acetylene complex [Me<sub>2</sub>SiCH<sub>2</sub>(C<sub>5</sub>Me<sub>4</sub>)<sub>2</sub>Ti(η<sup>2</sup>‐Me<sub>3</sub>SiC<sub>2</sub>SiMe<sub>3</sub>)] (<bold>3</bold>‐btmsa). Besides, tetramethyldisilyl‐ and dimethylsilyl‐bridged metallocene complexes (structural motif <bold>4</bold> and <bold>5</bold>, respectively) were prepared. All <italic>ansa</italic>‐titanocene alkyne complexes were reacted with stoichiometric amounts of water; the hydrolysis products were isolated as model complexes for the investigation of the elemental steps of overall water splitting. Compounds <bold>1</bold>, <bold>2</bold>‐btmsa, <bold>2</bold>‐(OH)<sub>2</sub>, <bold>3</bold>‐Cl<sub>2</sub>, <bold>3</bold>‐btmsa, <bold>4</bold>‐(OH)<sub>2</sub>, <bold>3</bold>‐alkenyl and <bold>5</bold>‐alkenyl were characterised by X‐ray diffraction analysis.</p> </abstract>