Mechanistic studies of processes involving carbon-carbon bond cleavage in gas-phase organometallic reactions using product kinetic energy release distributions: Co+ reacting with cyclopentane

Abstract

A reverse-geometry mass spectrometer is used to obtain product ion kinetic energy release distributions to probe the energetics and mechanisms of several gas-phase organometallic reactions. In particular, we examine the mechanism for C{sub 2}H{sub 4} and C{sub 3}H{sub 6} elimination from Co(cyclopentane){sup +}. The kinetic energy release distribution associated with these processes can be modeled by using phase space calculations assuming, for the C{sub 3}H{sub 6} elimination process, propene rather than cyclopropane is being eliminated as the product neutral, and for the C{sub 2}H{sub 4} elimination process, Co(propene){sup +} rather than (cobaltacyclobutane){sup +} is being formed as the product ion. In addition, we obtain a heat of formation for the cobalt ethylene ion of 255 kcal/mol at 0 K, corresponding to a bond dissociation energy of 42 kcal/mol at 0 K, by fitting the theoretical results to the experimental distribution.