Sodium • 15-crown-5

Other names: 1,4,7,10,13-penta­oxa­cyclo­penta­dec­ane sodium cation

C₁₀H₂₀O₅ • Na⁺

23/50 common

The "crown ethers" (so named for their visual resemblance to a crown when viewed in 3 dimensions) are a group of cyclic ether compounds of significant chemical interest due to their ability to strongly bind certain cations within the center of their ring through the lone pairs in their oxygen atoms. Their affinity for various cations is dictated primarily by the diameter of their central cavity, and as such specific crown ethers are applied to selectively complexate and sequester target cations based on their cationic radius. The 15-crown-5 depicted here is utilized for its selectivity towards sodium ions over other alkali cations.