18-Crown-6

• Catalog No.: A11249
• CAS Number: 17455-13-9
• M. F.: C12H24O6
• M. W.: 264.31536
• Purity: 99%

SYNONYMS

• Title: 18-冠-6醚
• IUPAC name: 1,4,7,10,13,16-hexaoxacyclooctadecane
• IUPAC Traditional name: 18-crown-6 ether
• Synonyms: 1,4,7,10,13,16-Hexaoxacyclooctadecane

DATABASE IDS

• Beilstein Number: 1619616
• EC Number: 241-473-5
• CAS Number: 17455-13-9
• MDL Number: MFCD00005113
• Merck Index: 142602

PROPERTIES

• Purity: 99%
• Boiling Point: 116°C/0.2mm
• Density: 1.175
• Flash Point: 109°C(228°F)
• Melting Point: 37-41°C
• GHS Hazard statements: H302-H319-H313
• European Hazard Symbols: X
• GHS Precautionary statements: P280-P305+P351+P338-P301+P312-P312-P337+P313-P501A
• Risk Statements: 22-36
• RTECS: MP4500000
• Safety Statements: 26-36
• Storage Warning: Hygroscopic
• TSCA Listed: 是

REFERENCES

• Crown ether (see Appendix 2) 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, A13104: Synthesis, 382 (1986). N-Alkylation of Glutarimide, L00968, and Succinimide, A13503: 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), the condensation of nitromethane with aldehydes: Tetrahedron Lett., 3219 (1978), and the transesterification of diaryl to dialkyl phosphonates: Synthesis, 409, 412 (1982).
• Crown ether catalysis can be used in the reaction of KCN with alkyl halides to give nitriles: Tetrahedron Lett., 71 (1975), and for the preparation of acyl cyanides from acid chlorides: Tetrahedron Lett., 21, 2959 (1980). The 1:1 complex between 18-crown-6 and KCN has been used catalytically in the cyanosilylation of aldehydes, ketones and quinones with TMSCN; for examples, see: Org. Synth. Coll., 7, 517 (1990).
• Has been widely used in alkylation reactions with, e.g. K₂CO₃ as base: