Development of the methodrogy for remote controled asymmetric synthesis in [3,3]-Sigmatropic Rearrangement

点击翻译按钮获取中文摘要

The Ireland-Claisen rearrangement of the enolates of allylesters, frequently used for the stereocontrolled C-C bond formation, is not suited for the substrate-controlled asymmetric induction. In order to cover the shortcoming, we investigated the thermal rearrangement of amide enolates and found that 1) the enolate derived from N-(2E)-buteny1-N-buty1propanamide rearranged with excellent intermal asymmetric induction (syn : anti = 199 : 1), that 2) the reaction of those containing chiral alkyl groups on the nitrogen proceeded with high selectivity (up to 19 : 1) in relative asymmetric induction, and that 3) the rearrangement can satisfactorily be extended to the acetamides with a heteroatom at the alpha-position. 4) Utilyzing the reaction, (-)-verrucarinolactone, D-allo-isoleucine, and (-)-isoiridomyrmecin were synthesized with excellent stereoselectivity in short steps.