2 results
Search Results
Now showing 1 - 2 of 2
- ItemSynthesis and crystallographic characterization of [2,2-bis(η5-pentamethylcyclopentadienyl)-3,4-bis(trimethylsilyl)-2-zirconafuran-5-one-κO5]triisobutylaluminium(Chester : International Union of Crystallography, 2018-3-27) Burlakov, Vladimir V.; Bogdanov, Vyacheslav S.; Arndt, Perdita; Spannenberg, Anke; Rosenthal, Uwe; Beweries, Torsten; Shur, Vladimir B.The crystal structure of the title zwitterionic zirconocene complex containing a furanone unit, [AlZr(C10H15)2(C4H9)3(C9H18O2Si2)], is reported. On reacting a zirconafuranone with two equivalents of HAl(i-Bu)2, disproportionation of the Lewis acid results in the formation of a triisobutylaluminium fragment, Al(i-Bu)3, which coordinates to the exocyclic carbonyl O atom of the zirconafuranone ring. Single-crystal X-ray diffraction reveals that the zirconafuranone ring remains intact with coordination of the aluminium to the exocyclic O atom. One of the i-butyl groups is disordered over two sets of sites, with an occupancy ratio of 0.731 (3):0.269 (3).
- Item1-Titanacyclobuta-2,3-diene-an elusive four-membered cyclic allene(Cambridge : RSC, 2019) Reiß, Fabian; Reiß, Melanie; Bresien, Jonas; Spannenberg, Anke; Jiao, Haijun; Baumann, Wolfgang; Arndt, Perdita; Beweries, TorstenThe synthesis of an unusual 1-metalla-2,3-cyclobutadiene complex [rac-(ebthi)Ti(Me3SiC3SiMe3)] (rac-ebthi = rac-1,2-ethylene-1,1′-bis(η5-tetrahydroindenyl)), a formal metallacyclic analogue of a non-existent four-membered 1,2-cyclobutadiene, is described. By variation of the cyclopentadienyl ligand of the titanocene precursor it was possible to stabilise this highly exotic compound which selectively reacts with ketones and aldehydes to yield enynes by oxygen transfer to titanium. Analysis of the bonding and electronic structure of the metallacycle shows that the complex is best described as an unusual antiferromagnetically coupled biradicaloid system, possessing a formal Ti(iii) centre coordinated with a monoanionic radical ligand. © 2019 The Royal Society of Chemistry.