Room-temperature palladium(II)-catalyzed N-vinylation of sulfonamides and acylamides with vinyl acetate as vinyl source
摘要:
Room-temperature N-vinylation of various substituted sulfonamides and acylamides with vinyl acetate was achieved for the first time with a palladiumicarbene catalyst system. This reaction provides a useful method for synthesis of enamides under mild conditions. (C) 2010 Elsevier Ltd. All rights reserved.
Room-temperature N-vinylation of various substituted sulfonamides and acylamides with vinyl acetate was achieved for the first time with a palladiumicarbene catalyst system. This reaction provides a useful method for synthesis of enamides under mild conditions. (C) 2010 Elsevier Ltd. All rights reserved.
Enantioselective Synthesis of α-Aryl-β-Aminocyclopropane Carboxylic Acid Derivatives via Rh(II)-Catalyzed Cyclopropanation of Vinylsulfonamides with α-Aryldiazoesters
of α-aryl-β-aminocyclopropane carboxylic acidderivatives bearing one quaternary carbon stereogenic center vicinal to the amino-substituted carbon in high yields with excellent diastereo- and enantioselectivities. Vinylsulfonamides showed complementary advantages over the well-developed vinylamides or vinylcarbamates for this Rh(II)-catalyzed cyclopropanation strategy. Moreover, these conformationally
已经报道了乙烯基磺酰胺与衍生自α-芳基重氮酯的供体-受体卡宾的反应,由叔丁基甘氨酸衍生的二铑络合物Rh 2 ( S -4-Br-NTTL) 4催化。该方法以高产率提供了多种α-芳基-β-氨基环丙烷羧酸衍生物,该衍生物具有一个与氨基取代的碳相邻的季碳立体中心,具有优异的非对映和对映选择性。对于这种 Rh(II) 催化的环丙烷化策略,乙烯基磺酰胺与成熟的乙烯基酰胺或乙烯基氨基甲酸酯相比显示出互补优势。此外,这些构象受限的α-芳基-β-氨基环丙基羧酸衍生物可以很容易地结合到二肽中。