| 摘要 |
This invention concerns a compound of formula (I) wherein: R<1> and R<2> are each independently hydrocarbyl or substituted hydrocarbyl; X<1> is an element or substituted element more electronegative than carbon; and X<2> is an element more electronegative than carbon, a substituted element more electronegative than carbon, hydrogen, hydrocarbyl, substituted hydrocarbyl or an inert functional group. A process for making these carbenes is also disclosed. The carbenes are useful in various catalysts and as ligands in transition metal compounds. |
