Ch. Winter et al., MULTIPLE DESILYLATION OF SILYLATED CYCLOPENTADIENES PROMOTED BY IONICRUTHENIUM AND RHODIUM HALIDES, Inorganic chemistry, 32(17), 1993, pp. 3654-3659
The reactivity of hydrated ruthenium trichloride and hydrated rhodium
trichloride toward silylated cyclopentadienes was investigated. Treatm
ent of ruthenium trichloride with (trimethylsilyl)cyclopentadiene, bis
(trimethylsilyl)cyclopentadiene, or tris(trimethylsilyl)cyclopentadien
e in alcohol solvents afforded ruthenocene in 85-96% isolated yields.
GLC analysis of these reactions, as well as the reactions of benzyltri
ethylammonium chloride with (trimethylsilyl)cyclopentadiene, bis(trime
thylsilyl)cyclopentadiene, and tris(trimethylsilyl)cyclopentadiene, re
vealed a novel chloride ion-induced desilylation of the silylated cycl
opentadienes. These experiments demonstrated that the silylated cyclop
entadienes were completely desilylated by chloride ion to afford cyclo
pentadiene, which then reacted with the ruthenium ion to afford ruthen
ocene. Treatment of hydrated rhodium trichloride with (trimethylsilyl)
cyclopentadiene or cyclopentadiene monomer afforded cyclopentadienylrh
odium dichloride oligomer in 93% and 82% yields, respectively. Treatme
nt of hydrated rhodium trichloride with bis(trimethylsilyl)cyclopentad
iene afforded cyclopentadienylrhodium dichloride oligomer (27%) and (t
rimethylsilyl)cyclopentadienylrhodium dichloride dimer (70%). The stru
cture of (trimethylsilyl)cyclopentadienylrhodium dichloride dimer was
determined, showing that this compound crystallized in the triclinic s
pace group P1BAR with cell dimensions a = 10.797(6) angstrom, b = 11.2
04(4) angstrom, c = 11.335(3) angstrom, alpha = 79.23(2)-degrees, beta
= 70.28(3)-degrees, gamma = 64.75(3)-degrees, V = 1166.0(8) angstrom3
, and Z = 2.