IMes

IMes
Names
	Preferred IUPAC name 1,3-Bis(2,4,6-trimethylphenyl)-1,3-dihydro-2H-imidazol-2-ylidene
	Other names 1,3-Dimesitylimidazol-2-ylidene, 1,3-bis(2,4,6-trimethylphenyl)-imidazolium, 1,3-bis(2,4,6-trimethylphenyl)imidazol-2-ylidene
Identifiers
CAS Number	141556-42-5 ;
3D model (JSmol)	Interactive image;
ChemSpider	9298886;
ECHA InfoCard	100.154.201
PubChem CID	11123757;
CompTox Dashboard (EPA)	DTXSID70456010 ;
	InChI InChI=1S/C21H24N2/c1-14-9-16(3)20(17(4)10-14)22-7-8-23(13-22)21-18(5)11-15(2)12-19(21)6/h7-12H,1-6H3 Key: JCYWCSGERIELPG-UHFFFAOYSA-N; InChI=1/C21H24N2/c1-14-9-16(3)20(17(4)10-14)22-7-8-23(13-22)21-18(5)11-15(2)12-19(21)6/h7-12H,1-6H3 Key: JCYWCSGERIELPG-UHFFFAOYAJ;
	SMILES Cc1cc(c(c(c1)C)N2C=CN([C]2)c3c(cc(cc3C)C)C)C;
Properties
Chemical formula	C21H24N2
Molar mass	304.43
Appearance	white solid
Melting point	150 to 155 °C (302 to 311 °F; 423 to 428 K)
	Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

IMes is an abbreviation for an organic compound that is a common ligand in organometallic chemistry. It is an N-heterocyclic carbene (NHC). The compound, a white solid, is often not isolated but instead is generated upon attachment to the metal centre.

First prepared by Arduengo, the heterocycle is synthesized by condensation of 2,4,6-trimethylaniline and glyoxal to give the diimine. In the presence of acid, the resulting glyoxal-bis(mesitylimine) condenses with formaldehyde to give the dimesitylimidazolium cation. This cation is the conjugate acid of the NHC.