Photolytic C–H activation and dehydrogenation of alkanes at cyclopentadienyl iridium complexes in a perfluorinated solvent
Abstract
The fluorinated complex [(Cpf)Ir(CO)2] (2) [Cpf = C5H4(CH2)2(CF2)5CF3] serves as a precursor for the photolytic activation of C–H bonds in alkanes to give [(Cpf)Ir(CH3)(H)(CO)] (3), [(Cpf)Ir(C5H9)(H)(CO)] (4), [(Cpf)Ir(C6H11)(H)(CO)] (5) or [(Cpf)Ir(C8H15)(H)(CO)] (6). In C7F14 as a solvent the latter react to yield the corresponding olefins as well as [(Cpf)Ir(H)2(CO)] (7). Photocatalytic experiments revealed that [(Cpf)Ir(CO)2] (2) and the non-fluorinated compound [(Cp)Ir(CO)2] (1) dehydrogenate cyclohexane in C7F14. In C6H12 as a solvent a decomposition of the catalysts was observed.