Solvent-free and catalyst-free direct alkylation of alkenes

A convenient method for synthesizing aryl-containing trisubstituted alkenes through direct alkylation of alkenes was successfully achieved under solvent-free and catalyst-free conditions. The absence of solvents was found to be crucial in initiating this sequence. Moreover, this protocol stands out due to its minimal waste production and straightforward operation. The radical capture experiment provided evidence for an ionic reaction mechanism.