Diversification of Nucleophile-Intercepted Beckmann Fragmentation Products and Related Density Functional Theory Studies
2020
Lowder, Leah L. | Zhao, Fengyue | Vaughan, Mathes M. | Houk, K. N. | Liu, Fang | Wu, Jimmy
The nucleophile-intercepted Beckmann fragmentation (NuBFr) has the potential to be broadly applicable to the synthesis of indoline alkaloid-based natural products. However, the reaction has not been widely adopted, in part, because of limitations associated with the availability of appropriate promoter–Nu reagents. We have devised a stereospecific Ag(I)-promoted reaction for functionalizing NuBFr products to give novel compositions of matter that may be useful in synthesis and medicinal chemistry. With unhindered amine nucleophiles, structurally unique [2.2.2]-bicycloamidines are generated. We also disclose for the first time detailed density functional theory studies, which shed light on the mechanism of the NuBFr and Ag-promoted substitution reaction that supports an unusual aziridinium ion as a key intermediate.
显示更多 [+] 显示较少 [-]