Phosphonium and arsonium salts based on alantolactone

The reaction of alantolactone, a sesquiterpene α,β-unsaturated lactone, with H-phosphonium or H-arsonium triflates proceeds as P–H or As–H addition at the terminal =CH₂ moiety to afford novel triphenyl(sesquiterpenyl)phosponium or -arsonium triflates. Their diastereoisomerism at the formed C¹¹ chiral center has been simulated by quantum chemical calculations.