Crown ethers are not the only macrocyclic ligands that have affinity for the potassium cation.
12.
The crown ethers are examples of small polyethers.
13.
Lithium ions may be chemically removed by binding to species such as cryptands or crown ethers.
14.
Basically, it was research on a crown ether compound, a biological mimic of an ion channel,
15.
Such salts can be isolated by the addition of macrocyclic ligands such as crown ether and cryptands.
16.
This process is accompanied by an increase in emission intensity at 343 nm resulting from freed crown ether.
17.
The breakthrough came in the 1960s with the synthesis of the crown ethers by Charles J . Pedersen.
18.
Charles J . Pedersen won the 1987 Nobel Prize in Chemistry for his methods of synthesizing crown ethers.
19.
Reaction of benzoquinone with trimethylsilylcyanide, catalyst KCN is introduced as a 1 : 1 complex with the Crown ether 18-crown-6
20.
In 1984 Olmstead presented the lithium crown ether salt of the triphenylmethyl carbanion from triphenylmethane, n-butyllithium and 12-crown-4 at low temperatures:
