Eschenmoser's salt

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Eschenmoser's salt
Eschenmoser's salt
Names
IUPAC name
Dimethyl(methylidene)ammonium iodide
Identifiers
3D model (JSmol)
ChemSpider
ECHA InfoCard 100.046.968 Edit this at Wikidata
UNII
  • InChI=1S/C3H8N.HI/c1-4(2)3;/h1H2,2-3H3;1H/q+1;/p-1 checkY
    Key: VVDUZZGYBOWDSQ-UHFFFAOYSA-M checkY
  • InChI=1/C3H8N.HI/c1-4(2)3;/h1H2,2-3H3;1H/q+1;/p-1
    Key: VVDUZZGYBOWDSQ-REWHXWOFAW
  • C[N+](C)=C.[I-]
  • [I-].[N+](=C)(C)C
Properties
C3H8NI
Molar mass 185.01 g/mol
Appearance colorless hygroscopic crystals
Melting point 116 °C (241 °F; 389 K)
decomposes
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
☒N verify (what is checkY☒N ?)

Eschenmoser's salt, dimethyl(methylidene)ammonium iodide, is a strong dimethylaminomethylating agent, used to prepare derivatives of the type RCH
2
N(CH
3
)
2
.[1][2] Enolates, enolsilylethers, and even more acidic ketones undergo efficient dimethylaminomethylation. Once prepared, such tertiary amines can be further methylated and then subjected to base-induced elimination to afford methylidenated ketones. The salt was first prepared by the group of Albert Eschenmoser[3] after whom the reagent is named.

Analogous salts, dimethyl(methylidene)ammonium chloride (Böhme's salt[1], after Horst Böhme) and trifluoroacetate, have similar properties and applications.[1]

See also

References

  1. ^ a b c E. F. Kleinman in "Dimethylmethyleneammonium Iodide and Chloride" in Encyclopedia of Reagents for Organic Synthesis (Ed: L. Paquette) 2004, J. Wiley & Sons, New York. doi:10.1002/047084289X.rd346
  2. ^ Horst Böhme; Eberhard Mundlos; Otto-Erich Herboth (1957). "Über Darstellung und Eigenschaften α-Halogenierter Amine". Chemische Berichte. 90 (9): 2003–2008. doi:10.1002/cber.19570900942.
  3. ^ Jakob Schreiber; Hans Maag; Naoto Hashimoto; Albert Eschenmoser (1971). "Dimethyl(methylene)ammonium Iodide". Angewandte Chemie International Edition in English. 10 (5): 330–331. doi:10.1002/anie.197103301.