Density functional theory was used to investigate the kinetics of the reaction of addition Of C2H3 and C6H5 to 1,3-C4H6. Kinetic constants for each elementary reaction involved in the reactive processes were calculated at the B3LYP/6-31g(d,p) level with conventional transition state theory, while overall rate constants for the formation of the different products were determined with Quantum Rice Ramsperger Kassel theory. The main result of this study is that, once provided a significant amount of 1,3-C4H6 in the flame environment (such as in butadiene flames), a significant contribution to the rate of formation of benzene, cyclopentadiene, and naphthalene can be ascribed to the investigated reactions.