A Stable Crown Ether Complex with a Noble‐Gas Compound

Abstract Crown ethers have been known for over 50 years, but no example of a complex between a noble‐gas compound and a crown ether or another polydentate ligand had previously been reported. Xenon trioxide is shown to react with 15‐crown‐5 to form the kinetically stable (CH 2 CH 2 O) 5 XeO 3 adduct, which, in marked contrast with solid XeO 3 , does not detonate when mechanically shocked. The crystal structure shows that the five oxygen atoms of the crown ether are coordinated to the xenon atom of XeO 3 . The gas‐phase Wiberg bond valences and indices and the empirical bond valences indicate that the Xe‐ ‐ ‐O crown bonds are predominantly electrostatic and are consistent with σ‐hole bonding. Mappings of the electrostatic potential (EP) onto the Hirshfeld surfaces of XeO 3 and 15‐crown‐5 in (CH 2 CH 2 O) 5 XeO 3 and a detailed examination of the molecular electrostatic potential surface (MEPS) of XeO 3 and (CH 2 CH 2 O) 5 reveal regions of negative EP on the oxygen atoms of (CH 2 CH 2 O) 5 and regions of high positive EP on the xenon atom, which are also in accordance with σ‐hole interactions.