Synthesis, characterization, and single crystal X-ray diffraction studies of cis-Ph2C2H2(eta(5)-C5H4)(2)Ca(THF)(2)

cis-[(1,2-diphenyl-1,2-dicyclopentadienyl)ethanediyl]bis(tetrahydrofuran)ca lcium is prepared by reductively coupling phenylfulvene with activated calc ium to produce cis and trans isomers which can be separately crystallized. The cis isomer crystallizes in the monoclinic space group P2(1)/c. The cell parameters are: a = 9.7006(1), b = 18.9839(1), c = 14.2018(2) Angstrom, be ta = 91.263(1)degrees, V = 2614.70(5) Angstrom(3), D-calc = 1.252 mg/m(3), and Z = 4. Spectroscopic and crystallographic data for the cis-isomer are p resented and discussed.