Synthesis, Structure, Electrochemistry and Reactivity of the Bis(μ-σ-stannanediyl)dinickel Butterfly Cluster [{{(SiMe3)2CH}2Sn–Ni(η5-Cp)}2](Ni2–Sn2)
✍ Scribed by Jörg J. Schneider; Jörg Hagen; Dieter Bläser; Roland Boese; Fabrizia Fabrizi de Biani; Piero Zanello; Carl Krüger
- Publisher
- John Wiley and Sons
- Year
- 1999
- Tongue
- English
- Weight
- 402 KB
- Volume
- 1999
- Category
- Article
- ISSN
- 1434-1948
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✦ Synopsis
Addition of stannylene [{(SiMe 3 ) 2 CH} 2 Sn:] (2) to the unbridged water results in the cleavage of an Ni-Sn bond and subsequent opening of the cluster cage of 3 to form the trinuclear homobimetallic Ni-Ni bond of [{PEt 3 Ni(η 5 -Cp)} 2 ] (1) gives the heterobimetallic, tetranuclear compound [{{(SiMe 3 ) 2 CH} 2 Sn-compound [(η 5 -Cp)Ni{Sn(CH(SiMe 3 ) 2 } 2 OH] (6) having an Sn-OH-Sn bridge. The hydroxy proton in 6 can be exchanged by Ni(η 5 -Cp)} 2 ] (3) with a butterfly arrangement and leaves the Ni-Ni bond of 1 intact. Elimination of both PEt 3 ligands from deuterium within a few minutes, as determined by 1 H-NMR spectroscopy, giving the monodeuterio product, [D 1 ]-6. the starting material 1 is observed, probably due to steric restraints. Compound 3 is formally related to the hypothetical Compound 6 is reactive towards acetonitrile, leading to cleavage of one Ni-Sn bond, elimination of one closo-borane B 4 H 4 2-. The Ni-Ni bond in 3 is only slightly elongated [2.454(3) A ˚] when compared to the starting material [{(SiMe 3 ) 2 CH} 2 Sn:] unit, and formation of the organotin hydroxo complex [{(SiMe 3 ) 2 CH} 2 (OH)Sn-Ni(η 5 -Cp)(CH 3 CN)] 1 [2.41(1) A ˚]. Compound 3 displays a butterfly arrangement with a hinge angle of 62.
5°. An alternative route to 3 is by a (7). In this complex, acetonitrile is coordinated to Ni via its σ lone pair, bearing the OH ligand in a terminal bonding mode direct reaction between nickelocene (5) and Lappert's stannylene [{(SiMe 3 ) 2 CH} 2 Sn:] in 63% yield. Treating 3 with to tin.