(Amino)(aryl)carbenes: Stable singlet carbenes featuring a spectator substituent

Several (amino)(aryl)carbenes have been shown to be stable at room temperat ure in solution and in the solid state. Electroneutrality of the carbene ce nter is ensured by the amino group, which has both pi -donor and sigma -acc eptor electronic character. The aryl group remains a spectator substituent, as shown by single-crystal x-ray analysis and by its chemical behavior. Be cause only one electron-active substituent is needed, numerous stable carbe nes will become accessible, which will open the way for new synthetic devel opments and applications in various fields.