TRINDANE-RUTHENIUM SANDWICH COMPLEXES - AN NMR AND X-RAY CRYSTALLOGRAPHIC STUDY OF [(TRINDANE)RUCL2](2), (TRINDANE)RUCL2[P(OME)(3)], AND [(TRINDANE)(2)RU][BF4](2)

Trindane and [(p-cymene)RuCl2](2) react in the melt to yield [(trindan e)RuCl2](2) (4), the NMR spectra of which reveal the presence of [{(tr indane)Ru}(2)(mu-Cl)(3)]Cl (6) in solution. The X-ray crystal structur e of 4 reveals that two of the cyclopentene rings adopt endo envelope conformations, while the third five-membered ring is folded in an exo fashion to avoid a terminal chlorine in the other half of the dimer. B ridge cleavage with trimethyl phosphite gives (trindane)RuCl2[P(OMe)(3 )] (8), and the X-ray crystal structure shows that all three periphera l rings are folded such that the wingtip methylene groups are oriented toward the metal. Finally, treatment of 4 with excess trindane in the presence of AgBF4 yields the dicationic sandwich compound [(trindane) (2)Ru](2+) 2BF(4)(-)(3).