IMes

{{Chembox

| ImageFile = 1,3-bis(2,4,6-trimethylphenyl)imidazol-2-ylidene (aka IMes).png

| ImageSize =

| ImageAlt =

| PIN = 1,3-Bis(2,4,6-trimethylphenyl)-1,3-dihydro-2H-imidazol-2-ylidene

| OtherNames = 1,3-Dimesitylimidazol-2-ylidene, 1,3-bis(2,4,6-trimethylphenyl)-imidazolium, 1,3-bis(2,4,6-trimethylphenyl)imidazol-2-ylidene

|Section1={{Chembox Identifiers

| CASNo = 141556-42-5

| CASNo_Ref = {{cascite|correct|CAS}}

| PubChem = 11123757

| ChemSpiderID = 9298886

| SMILES = Cc1cc(c(c(c1)C)N2C=CN([C]2)c3c(cc(cc3C)C)C)C

| 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

| InChIKey = JCYWCSGERIELPG-UHFFFAOYAJ

| StdInChI = 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

| StdInChIKey = JCYWCSGERIELPG-UHFFFAOYSA-N}}

|Section2={{Chembox Properties

| Formula = C₂₁H₂₄N₂

| MolarMass = 304.43

| Appearance = white solid

| Density =

| MeltingPtC = 150 to 155

| MeltingPt_notes =

| BoilingPt =

| Solubility = }}

|Section3={{Chembox Hazards

| MainHazards =

| FlashPt =

| AutoignitionPt =

}}

}}

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,{{cite journal | doi = 10.1021/ja00040a007| title = Electronic stabilization of nucleophilic carbenes| year = 1992| last1 = Arduengo| first1 = Anthony J.| last2 = Dias| first2 = H. V. Rasika| last3 = Harlow| first3 = Richard L.| last4 = Kline| first4 = Michael| journal = Journal of the American Chemical Society| volume = 114| issue = 14| pages = 5530–5534}} 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.{{cite journal | doi = 10.1021/ed300243s| title = Synthesis of Well-Defined Copper N-Heterocyclic Carbene Complexes and Their Use as Catalysts for a "Click Reaction": A Multistep Experiment That Emphasizes the Role of Catalysis in Green Chemistry| year = 2012| last1 = Ison| first1 = Elon A.| last2 = Ison| first2 = Ana| journal = Journal of Chemical Education| volume = 89| issue = 12| pages = 1575–1577| bibcode = 2012JChEd..89.1575I}}{{cite journal| title=Late-Stage Deoxyfluorination of Phenols with PhenoFluorMix |first1=Junting |last1=Chen |first2=Tobias |last2=Ritter |journal=Org. Synth. |year=2019 |volume=96 |page=16 |doi=10.15227/orgsyn.096.0016 |doi-access=free}}