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7737025 
Journal Article 
Synthesis and reactivity of silicon- and germanium-bridged ansa-cycloheptatrienyl-cyclopentadienyl titanium complexes 
Dd, DC; Jean, JM; Rosenthal, SJ; Ruggiero, AJ; Yang, D; Fleming, GR; Tamm, M; Kunst, A; Bannenberg, T; Randoll, S; Jones, PG 
2007 
1 
Organometallics
ISSN: 0276-7333
EISSN: 1520-6041 
AMER CHEMICAL SOC 
WASHINGTON 
26 
2 
417-424 
English 
WOS:000243339300023 
A new type of ansa-cycloheptatrienyl-cyclopentadienyl complex with germanium as a bridging atom has been synthesized. Using the established route for the formation of [(η-C5H4)Me2Si(η- C7H6)Ti], [1]-silatroticenophane 1, the analogous germylene-bridged derivative [(η-C5H4)Me 2Ge(η-C7H6)Ti] (2) has been isolated from the reaction of [(η-C7H7)Ti(η-C5H 5)] (troticene) with n-butyllithium/N,N,N′,N′- tetramethylethylenediamine (tmeda) in hexane and subsequent treatment of the intermediate dilithio complex with dimethyl(dichloro)germane. [1]Germatroticenophane 2 has been isolated in yields up to 15-20% and was characterized by means of 1H, 13C NMR spectroscopy, elemental analysis, and mass spectrometry. In addition, an X-ray diffraction study on a single crystal of 2 has been performed, and the structural characteristics are discussed in comparison to related ansa-compounds. The differential scanning calorimetry trace of 2 shows a strong exotherm at about 130°C, which is the result of a thermally induced ring-opening polymerization reaction, and a strain energy of about 45 kJ mol-1 has been determined. The reaction of 2 with equivalent amounts of tris(triethylphosphine)platinum(0) involves a regioselective insertion of a [Pt(PEt3)2] moiety into the germanium-carbon bond at the C7H6 site, yielding the [2]platinasilagermatroticenophane [(η-C5H4)Me2GePt(PEt3) 2(η-C7H6)Ti] (10), which was characterized by 1H, 13C, 31P, and 195Pt NMR spectroscopy. In addition, the reactivity of 1 toward protic acids such as HCl and HBF4 has been investigated, yielding complexes of the type [(η-C7H7)Ti(η-C5H4SiMe 2X)] (X = Cl, F) by exclusive cleavage of the Si-C7H 6 silicon-carbon bond and protonation of the cycloheptatrienyl ipso-carbon atom. © 2007 American Chemical Society.