Racemic 7-oxabi­cyclo­[2.2.1]­heptane-5-exo-iodo-6-endo-hydroxy-2-endo-carboxyl­ic acid-γ-lactone

The crystal structure of the γ-lactone of racemic 7-oxabi­cyclo­[2.2.1]­heptane-5-exo-iodo-6-endo-hydroxy-2-endo-carboxyl­ic acid has confirmed the position of the lactone bridge as 2–6 and the exo-iodo substituent configuration as previously proposed from chemical and ¹³C NMR evidence. The iodo substituent is also involved in a short non-bonding intermolecular interaction [I⋯O 3.289 (5) Å] with the non-bridging lactone oxy­gen giving polymeric chains which link weakly hydrogen-bonded (C—H⋯O) centrosymmetric dimer units.