17455-13-9 1,4,7,10,13,16-Hexaoxacyclooctadecane (18-Crown-6)

Flash point	109°(228°F)(lit.)
Boiling point	116°/0.2mm(lit.)
Density	1.175(lit.)
Storage	+4℃/Moisture sensitive

Crown ether mainly used to complex potassium ions. For a comprehensive study of solvent effects on complexation with K ions in a wide range of solvents, see: J. Org. Chem., 61, 5221 (1996).
Promotes methylation reactions with Dimethyl- carbonate: Synthesis, 382 (1986). N-Alkylation of Glutarimide, and Succinimide: Bull. Soc. Chim. Fr., 227 (1992).
Enables KH to metallate aryl-substituted methanes directly: J. Am. Chem. Soc., 99, 4457 (1977). In the presence of KOH in DME, various arylmethanes, benzyl alcohols and aldehydes are oxidized to carboxylic acids by molecular oxygen: Tetrahedron Lett., 25, 4989 (1984).
Has been used with KF to enhance the reactivity of F- as a base or a nucleophile, e.g. to promote Michael additions in aprotic solvents: J. Chem. Soc., Chem. Commun., 237 (1977)