Aza-crown ether

[5] The synthesis of aza crown ethers are subject to the challenges associated with the preparation of macrocycles.

[5] By reaction with tosyl chloride, diethylene triamine is converted to a derivative with two secondary sulfonamides.

Cryptands, three-dimensional aza crowns, feature tertiary amines.

Another large class of macrocyclic ligands feature both ether and amines..[8] One example is the diaza-18-crown-6, [(CH2CH2O)2(CH2CH2NH)]2.

[9] The presence of the amine allows the formation of Lariat crown ethers, which feature sidearms that augment complexation of cation.

The structure of [Co(III)(CH 2 CH 2 NH) 6 ] 3+ . [ 1 ] Color code: blue = N, gray = C, black = C, white = H.