AbstractOptically active β‐hydroxy sulfonamides and β‐hydroxy sulfones are very important building blocks for the preparation of bioactive compounds and pharmaceuticals. In this work, a highly efficient asymmetric hydrogenation of β‐keto sulfonamides and β‐keto sulfones has been developed using the phosphine‐free chiral ruthenium complex Ru(OTf)(TsDPEN)(η6‐p‐cymene) as the catalyst, to afford the corresponding β‐hydroxy sulfonamides and β‐hydroxy sulfones in high yields with excellent optical purities. In addition, a cascade asymmetric hydrogenation/dynamic kinetic resolution (DKR) of racemic cyclic β‐keto sulfonamides and β‐keto sulfones was also realized using the same catalyst, to give the corresponding chiral cyclic β‐hydroxy sulfonamides and β‐hydroxy sulfones in good yields with excellent enantio‐ and diastereoselectivities.magnified image
通过处理β-Ketosulfonamides从Boc或衍生Cbz-保护的氨基酸轴承疏水性侧链以良好至优异的收率制备Ñ烯丙基,Ñ烷基methanesulfonamides与Ñ正丁基锂,接着用的甲酯所得到的碳负离子的反应Ñ -保护的1-氨基酸。使用源自N的二价阴离子的类似反应-烷基甲磺酰胺的产率要低得多。在CsF存在下,在DMF中于室温下使用Selectfluor进行β-酮磺酰胺的亲电氟化,反应时间为15-60分钟,可提供良好产率的β-酮-α,α-二氟磺酰胺。使用cat可以良好的产率除去烯丙基保护基。Pd(PPh)3)4和二甲基巴比妥酸。当以Cs 2 CO 3为碱进行氟化反应时,衍生自Val,Leu或Ile的β-酮磺酰胺给出了预期的β-酮-α,α-二氟磺酰胺,而衍生自Ala,Phe或hPhe的β-酮磺酰胺给出了亚氨基β-酮-α,α-二氟磺酰胺的水合物。