Correction to “Cyclization Cascades Initiated by 1,6-Conjugate Addition”
Joshua L. Brooks, Alison J. Frontier
J. Am. Chem. Soc. 2012, 134, 16551–16553. DOI:10.1021/ja308451y
Page 16552-3. The structures of compounds 7-11 (Table 3) were assigned incorrectly. Recent experimental results indicate that products 7-11 are pyrans, constitutional isomers of the structures reported. The data suggest that pyran formation occurs via intramolecular enolate alkylation in cyclic acetoxonium species 13a, which is a geometrical isomer of proposed intermediate 13 (Scheme 2). A paper is in preparation that will provide a full explanation of the cyclization chemistry of dienyl diketones of type 4, including experimental data supporting the revised structure assignment of products 7-11.
