Given the preference in chemical biology for trifluoromethyl aryl diazirine reagents, the development of diazirine conjugates that can be activated using longer wavelengths of light would be highly desirable. However, it is unclear whether such an outcome is even possible through directly linking a diazirine group to a suitable chromophore. Certainly the way that diazirines are commonly drawn in the chemical literature, with four sigma bonds connected to the central carbon atom, suggests that-unlike azides, benzophenones, or linear diazo groups-cyclic diazirines are linked through a saturated atom. As such, one might not expect to see viable electronic conjugation from the chromophore to the diazirine LUMO, which needs to be populated in order to facilitate loss of N2 and generation of a carbene. This expected lack of conjugation, born from an expectation of sp 3 (or possibly sp ) hybridization at the central carbon of a diazirine, is likely the reason that no direct chromophore conjugates of trifluoromethyl diazirines have yet been reported. In this communication, we present a combination of computational, spectroscopic, and X-ray crystallographic evidence in support of the contention that the central carbon atom in a diazirine group is best described as being sp hybridized. While we acknowledge that orbital hybridization is merely a conceptual model, and need not have any bearing on the atoms themselves, the observation of p-orbital contribution from this carbon suggests the ready incorporation of diazirines onto light-harvesting pi systems. As a test-case for our hypothesis of diazirine-chromophore conjugation, we use a trifluoromethyl diazirine group as the electron-withdrawing motif in a classic 'push-pull' fluorene dye. We find that the resulting conjugate still functions as an effective chromophore, indicating that the diazirine group can replace a traditional conjugated electron-withdrawing group. Moreover, the diazirine-fluorene conjugate could be activated with 460 nm light to form a carbene capable of inserting into stable, unactivated C-H bonds. Finally, a two-photon activation using red light is also demonstrated for the first time on a trifluoromethyl aryl diazirine. Taken together, these data suggest a significantly expanded role for diazirines in target identification experiments requiring longer wavelength light sources.