Cracking and Dehydrogenation of Cyclohexane by [(phen)M(X)] (M = Ni, Pd, Pt; X = H, CH3) in the Gas Phase

Abstract

Gas-phase cationic ternary complexes of group 10 metals of the formula [(phen)M(X)]+, where phen = 1,10-phenanthroline (M = Ni, Pd, or Pt; and X = H or CH3), react with cyclohexane via C-H activation, forming the respective cyclohexyl species [(phen)M(c-C6H11)]+. Upon collisional activation, these species undergo two key competing processes: (i) ring opening followed by "cracking"of the hydrocarbon chain leading to extrusion of propylene and ethylene as major products among other hydrocarbons; and (ii) dehydrogenation of the cyclohexyl ring leading to the loss of one, two, or three hydrogen molecules, with subsequent loss of cyclohexenes or benzene. The relative prevalence of these two pathw..