A Stereodivergent Approach to (−)-α-Kainic Acid and (+)-α-Allokainic Acid Utilizing the Complementarity of Alkyne and Allene Cyclizations
作者:Maxim V. Chevliakov、John Montgomery
DOI:10.1021/ja993069j
日期:1999.12.1
A formalsynthesis of (+)-α-allokainic acid and a totalsynthesis of (−)-α-kainic acid were carried out using a short, efficient, and highly stereoselective approach. From an alkyne precursor, a nickel-catalyzed cyclization and a palladium-catalyzed rearrangement were utilized in the synthesis of (+)-α-allokainic acid. From an allene precursor, a nickel-catalyzed cyclization was utilized in the synthesis
Nickel and Palladium Catalysis in the Stereoselective Synthesis of Functionalized Pyrrolidines: Enantioselective Formal Synthesis of (+)-α-Allokainic Acid
products are accessible from 1 via the intermediate 2, which is obtained by Ni-catalyzed cyclization, transposition of the protectinggroup, and Pd-catalyzed reduction with allylic transposition. This stepwise formation of stereocenters allows a highly direct and stereoselective synthesis of the excitatory amino acid (+)-α-allokainic acid, which displays an all-trans arrangement of the substituents about the