The geometrical effect on the chemical reactivity of nucleophilic carbenes. A theoretical study

The reaction mechanism for the insertion of the nucleophilic carbenes into the C–H bond of methane has been investigated using the B3LYP/6-31G∗ level of theory. It is found that the singlet–triplet splitting of a carbene can be used as a diagnostic tool for the prediction of its reactivity. Our theoretical findings also suggest that stronger p(π) donor atoms bonded the carbene atom, and a more bent bond angle at the carbene center should enhance stability of carbenes. Theoretical data for 5- and 4-membered ring carbenes are compared.