Eschenmoser's salt

Eschenmoser's salt, dimethyl(methylidene)ammonium iodide, is a strong dimethylaminomethylating agent, used to prepare derivatives of the type RCH
₂N(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.

Eschenmoser's salt

Names
IUPAC name Dimethyl(methylidene)ammonium iodide
Identifiers
CAS Number	33797-51-2 (Iodide) Y 30354-18-8 (Chloride) N
3D model (JSmol)	Interactive image Interactive image
ChemSpider	2006292 Y
ECHA InfoCard	100.046.968
PubChem CID	2724133
UNII	5C42I004S1 Y
CompTox Dashboard (EPA)	DTXSID10369115
InChI InChI=1S/C3H8N.HI/c1-4(2)3;/h1H2,2-3H3;1H/q+1;/p-1 Y Key: VVDUZZGYBOWDSQ-UHFFFAOYSA-M Y InChI=1/C3H8N.HI/c1-4(2)3;/h1H2,2-3H3;1H/q+1;/p-1 Key: VVDUZZGYBOWDSQ-REWHXWOFAW
SMILES C[N+](C)=C.[I-] [I-].[N+](=C)(C)C
Properties
Chemical formula	C3H8NI
Molar mass	185.01 g/mol
Appearance	colorless hygroscopic crystals
Melting point	116 °C (241 °F; 389 K)
Solubility in water	decomposes
Hazards
R-phrases (outdated)	R36/37/38
S-phrases (outdated)	S26 S36
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
N verify (what is YN ?)
Infobox references

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