Formation and Crystal Structure of a Cationic Mono(cyclopentadienyl) Complex of Calcium, [(C₅Me₅)Ca(OPPh₃)₃]⁺I^-

Abstract

When the neutral Lewis base triphenylphosphine oxide reacts with (C 5 Me 5 )CaI(thf) 2 in THF, the halide is displaced from the calcium to generate the stable cation [(C 5 Me 5 )Ca(OPPh 3 ) 3 ] + . The latter exhibits a “piano stool” geometry and displays only modest air sensitivity.