A [4+4] annulation strategy for the synthesis of eight-membered carbocycles based on intramolecular cycloadditions of conjugated enynes
Author(s)Robinson, Julia M.; Tlais, Sami F.; Fong, Jennie; Danheiser, Rick Lane
MetadataShow full item record
A [4+4] annulation strategy for the synthesis of eight-membered carbocycles is reported that proceeds via a cascade involving two pericyclic processes. In the first step, the [4+2] cycloaddition of a conjugated enyne with an electron-deficient cyclobutene generates a strained six-membered cyclic allene that isomerizes to the corresponding 1,3-cyclohexadiene. In the second step, this bicyclo[4.2.0]octa-2,4-diene intermediate undergoes thermal or acid-promoted 6-electron electrocyclic ring opening to furnish a 2,4,6-cyclooctatrienone. The latter transformation represents the first example of the promotion of 6-electron electrocyclic ring opening reactions by acid.
DepartmentMassachusetts Institute of Technology. Department of Chemistry
Robinson, Julia M., Sami F. Tlais, Jennie Fong, and Rick L. Danheiser. “A [4+4] Annulation Strategy for the Synthesis of Eight-Membered Carbocycles Based on Intramolecular Cycloadditions of Conjugated Enynes.” Tetrahedron 67, no. 51 (December 2011): 9890–9898.
Author's final manuscript