Palladium catalysed queuing processes. Part 4: Termolecular cyclisation–anion capture cascades employing allene as a relay switch and secondary amines as nucleophiles
Pd(0) catalysed termolecular queuing processes involving oxidative addition to aryl or vinyl halides followed by cyclisation onto a proximate alkyne or alkene, allene (1 atm) insertion and capture of the resulting π-allyl palladium(II) species by secondary amines affords benzo-fused 5–8-membered rings in good yield.
Pd(0) catalysed termolecular queuing processes involving oxidative addition to aryl iodides followed by 5- or 6-exo-trig cyclisation, allene (1atm) insertion, and capture of the resulting π-allylpalladium(II) species by secondary amines occurs in good yield.