Chemical Properties
clear colorless to slightly yellow liquid after
Uses
It serves as an aprotic "solvent" for alkali metals, the sodium solution is a strong reducing agent.
Uses
12-Crown-4 can be used as:
- A promoter in the synthesis of poly(diethylsiloxane) (PDES) from monomer hexaethylcyclotrisiloxane using NaOH as a catalyst via anionic ring-opening polymerization.
- As an additive in the preparation of triarylmethane derivatives by palladium-catalyzed cross coupling reaction of aryl bromides with diarylmethane derivatives.
- A phase transfer catalyst in organic synthesis.
Definition
ChEBI: A crown ether that is cyclododecane in which the carbon atoms at positions 1, 4, 7 and 10 have been replaced by oxygen atoms.
General Description
12-Crown-4 is a crown ether generally used as a ligand in coordination chemistry. It is also known as lithium ionophore because of its strong chelating property specific to lithium cation.
Purification Methods
The distilled crude product has to be recrystallised from pentane at -20o to remove acyclic material. It is then dried over P2O5. It complexes Li. [Anet et al. Acta Chem Scand 27 3395 1973, Beilstein 19/11 V 334.]
