“…The cyclopentenyl ligand bridges one of the metal-metal edges in a µ,η 1 :η 2 manner. This bonding mode has been previously encountered, for example, in Os 4 (µ-H) 3 (CO) 11 -(µ,η 1 :η 2 -C 6 H 9 ), [2b,18] Os 4 (µ-H) 3 (CO) 11 (µ,η 1 :η 2 -CHCHPh), [19] Os 3 (µ-H)(CO) 10 (µ,η 1 :η 2 -CHCHCH 2 CH 3 ), Os 3 (µ-H)(CO) 10 (µ,η 1 :η 2 -CHCH 2 ), and Os 3 (µ-H)(CO) 10 (µ,η 1 :η 2 -CHCHPh).…”