インドールアルカロイド合成に向けた高ジアステレオ選択的２連続第４級炭素構築法の開発

抄録

Stereoselective C-C bond-forming reaction assembling quaternary carbon centers are of particular importance for synthesis of bioactive compounds. The challenge is exacerbated further when all-carbon quaternary stereocenters are adjacent. For construction of complex indole alkaloids, we now report that the efficient domino reactions (olefination, isomerization and high diastereoselective Claisen rearrangement) of (Z)- and (E)-2-(3',3'-disubstituted allyloxy)indolin-3-ones proceeded under mild conditions (-78ºC to rt) via preferential boat transition state to give (3R^*,3'R^*)- and (3R^*,3'S^*)-3-cyanomethyl-3-allylindolin-2-ones containing adjacent all-carbon quaternary stereocenters in high yields, respectively.

fig.1