A chiral C2 axially symmetric naphthalene derivative of a bi­cyclo­octane diketal

The crystal structure of the title compound, (−)‐(4R,5R,4′′R,5′′R)‐di­spiro­[4,5‐di­methyl‐1,3‐dioxalane‐2,3′‐[1′,5′‐(naphthalene‐1,8‐diyl)­bi­cyclo­[3.3.0]­octane]‐7′,2′′‐(4′′,5′′‐di­methyl‐1′′,3′′‐dioxalane)], C26H30O4, contains two independent mol­ecules in the asymmetric unit separated by normal van der Waals distances. The five‐membered rings in the trans‐2,3‐di­methyl‐1,4‐dioxa­spiro­[4.4]­nonane moieties exhibit envelope conformations and the acenaphthene moieties are essentially planar. The conformations of a dioxa­cyclo­pentane ring in the two mol­ecules are different. The molecular dimensions in both mol­ecules are as expected.