Complex sentence: In this preparation, dicyclopentadiene cracks to give cyclopentadiene, which reacts with Fe (CO) 5 concomitant with loss of CO. Thereafter, the pathways for the photochemical and thermal routes differ subtly but both entail formation of a hydride intermediate.
Split into simpler sentences: In this preparation, dicyclopentadiene cracks to give cyclopentadiene, which reacts with Fe (CO) 5. Cyclopentadiene reacts with Fe (CO) 5 concomitant with loss of CO. Thereafter, the pathways differ for the photochemical and thermal routes differ subtly but both entail formation of a hydride intermediate.