Uses
4-Nitrobenzo-15-crown-5 is a raw material used in synthesis as well as an intemediate in chemical syntheis and pharmaceutica intemediate. It is also used to separate cations, dissolve inorganic salts into organic solvents to perform naked anion chemistry, serve as phase transfer catalysts, and chiral crown ethers have been used to resolve racemic mixtures or separate isomers by chiral chromatography.
Purification Methods
Recrystallise the crown ether from EtOH, MeOH or *C6H6/hexane as for the 18-crown-6 compound below. It complexes with Na+, K+, NH4+, Ca2+, Mg2+ and Cd2+. The 1HNMR spectrum (CDCl3) has (ppm): 3.6-4.4 (m 16CH2), 6.8 (d 1H arom), 7.65 (d 1H arom), 7.80 (dd 1H arom Jab 9Hz and Jbc 3Hz) [Schmid et al. J Am Chem Soc 98 5198 1976, Kikukawa et al. Bull Chem Soc Jpn 50 2207 1977, Toke et al. Justus Liebigs Ann Chem 349 349, 761 1988, Lindner et al. Z Anal Chem 322 157 1985].
