Synthesis of cis-p-dioxano-12-crown-4 and X-ray crystallography of the (1:1) complex with lithium thiocyanate

Abstract

The synthesis of a novel 12-crown-4 analogue (cis-p-dioxano-12-crown-4 or cis-3,6,9,13,15- pentaoxabicyclo[9.3.1]pentadecane) is described. The (1:1) LiNCS complex crystallizes in the monoclinic Cc space group; a = 8.4973(2) Å, b = 18.0659(4) Å, c = 8.9168(1) Å, and β = 90.713(1)° with Z = 4. The crown adopts C1 symmetry to which the Li+ is coordinated in a rectangular pyramid with an apical -NCS.Key words: crown ethers, structure, complexation.