Germanium cyclopentadienyl complexes

A stabilized heteroleptic germanium cyclopentadienyl complex was obtained which has an extremely long (2.369(1) A) Ge-Cl bond and an 2-bound Cp ring (Equation (238)).309... 

Germanium-bridged complexes, with Zr(IV) and Hf(IV) cyclopentadienyl complexes, 4, 967 fluorenyl complexes, 4, 974 indenyl complexes, 4, 972... 

In a third class of 7t-cyclopentadienyl complexes, compounds of type LVIII are bound to a transition metal via the lone pair at the germanium atom. The first compounds in this series, the pentacarbonyl-[chloro(pentamethylcyclopentadienyl)germylene]chromium(0) (LIXa) and -tungsten(O) (LIXb) were synthesized by alkylation of the ylide complexes (CO)5M—GeCl2 THF according to Eq. (22) (201). Nucleophilic substitution reactions of LIXb lead to the alkyl- and amino-substituted complexes LIXc-e [Eq. (23)] (202). 

Bis(cyclopentadienyl) complexes CP2M (M = Ge, Sn, Pb) have been prepared by reaction of cyclopentadienylsodium and an appropriate dihalide in tetrahydro-furan. Electron diffraction shows that in the vapour these molecules have angular structures on account of the electron pair on the metal. In the solid state the germanium compound polymerizes within 3 h at ambient temperature, the tin compound within five days. The cyclopentadienyl groups are coordinated in a symmetrical pentahapto fashion (p. 191). Association through the rings occurs in the crystalline lead compound to give a polymeric chain structure (Fig. 4.8). 

Treatment of hydrogermanium cyclopentadiene transition metal complexes with LDA can lead initially to a competition between the deprotonation of the hydrogen linked to germanium or to the cyclopentadienyl ring, but a migration of the germyl group to cyclopentadiene was actually observed (equation 192)9. 

Trichloro(tripyridine)chromium(III), synthesis 36 Tris(3-bromoacetylacetonato)chromium(III), synthesis 37 Cyclopentadienyl tricarbonyl hydrides of chromium, molybdenum, and tungsten, synthesis 38 Trichloro(tripyridine)molybdenum(III), synthesis 39 Potassium octacyanotungstate(IV) 2-hydrate, synthesis 40 Chlorine(CP )-labeled thionyl chloride, silicon tetrachloride, boron chloride, germanium (IV) chloride and phosphorus(III) chloride, synthesis 44 Unipositive halogen complexes, synthesis 46 Monopyridineiodine(I) chloride, synthesis 47 Manganese(III) acetylacetonate, synthesis 49 Triiron dodecacarbonyl, synthesis 52... 

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