SIMes

SIMes (or H₂Imes) is an N-heterocyclic carbene. It is a white solid that dissolves in organic solvents. The compound is used as a ligand in organometallic chemistry. It is structurally related to the more common ligand IMes but with a saturated backbone (the S of SIMes indicates a saturated backbone). It is slightly more flexible and is a component in Grubbs II.^[1] It is prepared by alkylation of trimethylaniline by dibromoethane followed by ring closure and dehydrohalogenation.^[2]

SIMes

Names
IUPAC name 1,3-Bis(2,4,6-trimethylphenyl)-4,5-dihydroimidazol-2-ylidene
Other names IMesH2, H2IMes, 1,3-Dimesityl-imidazol-4,5-dihydro-2-ylidene
Identifiers
CAS Number	173035-11-5
3D model (JSmol)	Interactive image
ChemSpider	9403305
PubChem CID	11228257
CompTox Dashboard (EPA)	DTXSID20459319
SMILES Cc1cc(C)c(c(C)c1)N2CCN([C]2)c3c(C)cc(C)cc3C
Properties
Chemical formula	C21H26N2
Molar mass	306.453 g·mol−1
Melting point	79 to 85 °C (174 to 185 °F; 352 to 358 K)
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references