[(Ph3P)2ReH7] (Ia) reacted in tetrahydrofuran with cyclopentadiene or cyclohexa-1,4-diene under UV irradiation to give [(Ph3P)(eta-C5H5)ReH4] (II), and a 1:2 mixture of [(Ph3P)2(eta-C6H6)ReH] and [(Ph3P)(eta-C6H6)ReH3] (III), respectively; III was isolated from the photochemical reaction of Ia with 3,3-dimethylbutene in benzene. When using [(dppe)ReH7] (Ib) (dppe = Ph2PCH2CH2PPh2) instead of Ia in these three reactions, no cyclopentadienyl compound was obtained, but [(dppe)(eta-C6H6)ReH] (IV) and [(dppe)(eta-C6H6)ReCH2CH2CMe3] (V) were isolated; IV and V are precursors to arene and cyclohexadienylrhenium derivatives containing dppe.