Coupling molecules to a quantized radiation field inside an optical cavity creates a set of photonmatter hybrid states, called polaritons. These polariton states have a great promise to change chemical reactivity in a general and facile way by tuning the properties of matter as well as properties of photons. Despite the theoretical predictions of using polaritons for novel chemistry broadly, experimentally what has been demonstrated largely relates to polariton modified reaction kinetics. For example, collective couplings between the electronic excited states of fulgide or similar molecules and quantized photonic modes inside an optical cavity were shown to both enhance or suppress photochemical isomerization reactions. In another example, vibrational excitations collectively coupled to the photonic excitations of a microcavity, commonly referred to as vibrational strong coupling (VSC), resulted in chemical kinetics that can be enhanced or suppressed. In these two collective coupling regimes, the kinetics of the reactions are changed, but importantly there is no new type of product generated compared to the same reactions outside the cavity.