Palladium(0)-catalyzed cyclization of 6-(2-alkenyl)-2,7-octadienyl acetates (1) was carried out. When the 6-substituent is an allyl group, tandem cyclization of 1a has occurred to give trans-bicyclo[3.3.0]octane 2a. The compounds 1b-d having (E)- or(Z)-2-alkenyl groups at 6-position underwent the cyclization leading to 3b-d, which resulted from ß-elimination of the common 2-vinylcyclopentyl-methylpalladium intermediates. There was found an unprecedented cis diastereoselection at C(3)-C(6) of 1 during the cyclization as well as trans diastereoselection at C(6)-C(7) in the particular formation of 2a.
ASJC Scopus subject areas
- Organic Chemistry