Diphenyl ditelluride 2 has been found to add efficiently to various acetylenes 1 upon irradiation with visible light (>400 nm), providing vic-bis(phenyltelluro)alkenes 3 in good yields.
Alkylation of vic-bis(phenyltelluro)alkenes 1 with lithium dialkylcuprates takes place regioselectively at the terminal carbon of 1 to provide the corresponding 1-alkyl-2-phenyltelluroalkenes (2) stereoselectively in good yields.