Visible-light-induced 3+2 cycloadditions of donor/donor diazo intermediates with alkenes to achieve (spiro)-pyrazolines and pyrazoles

Visible-light-induced 3+2 cycloadditions of donor/donor diazo precursors with alkenes to afford pyrazoles and (spiro)pyrazolines have been reported. Mechanistic and DFT studies suggested the non-covalent interactions promote the reaction.