Catalysis is, without question, one of the most efficient and powerful strategies for engineering chemical reactions. In this context, the ground-breaking discovery disclosed in 1991; by Arduengo et al. through isolation of the first persistent singlet N-heterocyclic carbene (NHC). These “bottle-able” stable N-heterocyclic carbene led to numerous catalytic applications in organometallic chemistry as well as in the metal-free catalytic reaction for their electron-rich properties. In recent years, various such electron-rich main group species such as abnormal N-heterocyclic carbene (aNHC), mesoionic N-heterocyclic olefine (mNHO), mesoionic N- heterocyclic imine (mNHI), phosphinidene P(I), and bicyclic (alkyl)amino carbene (BICAAC) have been isolated. We are developing various catalytic reactions under metal-free conditions using these electron-rich main-group species. In particular, we are currently interested in developing activation of small and strong molecules such as CO2, SO2, N2O, and H2 and further converting them to value-added chemicals.