Ab initio and density functional theory (DFT) calculations have been used to investigate the feasibility of cycloaddition reactions of enaminones 1 with sulphene. Specifically, the geometry optimizations, frequency calculations and self-consistent reactionfield (SCRF) solvent simulations in combination with higher-quality relative energies carried out at the DFT level using the 6-31+G(d) basis set suggests that the product obtained is both thermodynamically and kinetically preferred, indicating the feasibility of this reaction. Additionally, experimental studies carried out on the reactions of these enaminones 1 with sulphene were also found to be in agreement with the theoretical predictions resulting in the synthesis of a variety of novel oxathiine derivatives having great biological and medicinal importance.Keywords: Enaminones, cycloadditions, sulphene, DFT, SCRFPDF and Supplementry file attached