Aza-Wacker-Type Reaction between Electron-Deficient Olefins and N-Alkylsulfonamides
摘要:
A palladium-catalyzed oxidative amination protocol of electron-deficient olefins by aza-Wacker-type reaction with N-alkylsulfonamides was developed. The presence of the stoichiometric amount of methanesulfonic acid was crucial for the success of this transformation. The reactions were conducted in green solvent under mild conditions and scalable with excellent E-type stereoselectivity. In addition, a Pd(II)/Pd(0) catalytic cycle with the existence of a very strong oxidant (Selectfluor) was proposed.
[2,3]-Wittig rearrangements of (E)-3-aza-allylic alcohol derivatives can provide access to functionalized 1,2-aminoalcohols with high syn or anti diastereoselectivity depending on the anionic stabilizing group (amide or alkyne).
PIFA-mediated ethoxyiodination of enamides with potassium iodide
作者:R. Beltran、S. Nocquet-Thibault、F. Blanchard、R. H. Dodd、K. Cariou
DOI:10.1039/c6ob01673a
日期:——
The combination of PIFA with KI in ethanol triggers the regioselective ethoxyiodination of a broad range of enamides with excellent yields and diastereoselectivities.
Iodine(III)-Mediated Umpolung of Bromide Salts for the Ethoxybromination of Enamides
作者:Sophie Nocquet-Thibault、Pascal Retailleau、Kevin Cariou、Robert H. Dodd
DOI:10.1021/ol400453b
日期:2013.4.19
Using (diacetoxylodo)benzene in conjunction with simple bromide salts in ethanol allows the regioselective ethoxybromination of a wide range of enamides, thus yielding highly versatile alpha-bromo hemiaminals, which can then be engaged in a broad array of transformations.