A Computational Study on the Photochemical O-H Functionalization of Alcohols with Diazoacetates.

In this computational study, we provide a detailed analysis of the underlying reaction mechanism and show that a singlet carbene is initially formed. Depending on the pKA of the alcohol, this singlet carbene can engage in direct protonation or enol formation to yield the O-H functionalization product. On the contrary, propargylic alcohols take up a dual role and form a complex with the carbene intermediate that leads to facile cyclopropenation reactions.