Abstract
The metal-catalyzed allylic substitution reaction of 5a,b and 6a was examined. Reaction with stabilized nucleophiles led to exclusive attack at the less-hindered allylic terminus, and the stereoselectivity varied with the bidentate ligand used but favored retention. The yields and reaction times were improved with the use of microwaves. Alkylation via transmetalation was only observed with phenyl- and vinylstannatranes and gave regio- and stereoselectivity opposite those observed with the stabilized anions. The epimeric carbonates 5a and 5b displayed very different reactivities. Catalysts containing metals other than palladium were completely unreactive and led to recovered starting material.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have