Cascade Pd(ii)-catalyzed Wacker lactonization–Heck reaction: rapid assembly of spiranoid lactones†
An unprecedented Pd-catalyzed cascade Wacker–Heck lactonization-cyclization sequence is reported. The process provides a facile approach to bi- and tricyclic spiranoid lactones in good yields. The reaction shows general substrate scope and a broad functional group tolerability. In addition, a rare 4-exo trig Heck-type cyclization is demonstrated.