A Mild Benzannulation through Directed Cycloaddition Reactions
作者:James D. Kirkham、Roger J. Butlin、Joseph P. A. Harrity
DOI:10.1002/anie.201200917
日期:2012.6.25
Simple as ABC: Alkynyl borane cycloadditions can be substrate‐directed to assemble aromatic difluoroboranes within an extremely mild and efficient reaction manifold compared to that of traditional methods (see scheme). The aromatic boranes are readily transformed into a range of useful products.
Cycloaddition reaction of methyl 2-pyronecarboxylates with 1,3-dienes
作者:T. Imagawa、A. Haneda、T. Nakagawa、M. Kawanisi
DOI:10.1016/0040-4020(78)80094-5
日期:1978.1
The experimental results of thermal cycloaddition reactions of methyl 2-pyrone-3-, 4-, 5- and 6-carboxylates with 1,3-dienes and the theoretical approach by a second order perturbation MO method are described. The sequential introduction of a methoxycarbonyl group onto a 2-pyrone ring caused a variety of selectivities in the cycloaddition reactions with 1,3-butadienes. PMO treatment based only on the
作者:Kohanov, Zachary A.、Shuvo, Suzzudul Islam、Lowell, Andrew N.
DOI:10.1021/acs.joc.4c01044
日期:——
intact pyrone (2H-pyran-2-one) into larger ring systems via annulation. In a formal [4 + 2] cycloaddition, the pyrone regioselectively accepts a benzylic anion as a nucleophile in a conjugate addition fashion, with the subsequent pyrone-derived enolate attaching to a pendant ester on the initial nucleophile. Subsequent base-driven enolate formation and elimination establish aromaticity of the newly formed