2H-Azirine-2-caboxamides have been designed to perform as a new type of bifunctional thiol linker under very mild reaction conditions. The cleavage of a C-N double bond of 2H-azirine furnishes an amino amide functional group in situ through a thiol addition and ring-opening process. It works with a broad scope of thiols and 2H-azirines in the absence of any catalysts at room temperature. Cysteine-containing
Cyclopeptide alkaloid model studies. A two-step conversion of 5-aminoisoxazoles to amino acid bis-amides
作者:Bruce H. Lipshutz、Deborah C. Reuter
DOI:10.1016/s0040-4039(00)82266-2
日期:——
Thermolyses of substituted 5-aminoisoxazoles, readily available from common starting materials, lead to azirines in good yields. Subsequent hydration affords -amide derivatives of amino acids.
A one-pot reaction to synthesize functionalized 2H-azirines through visible-light-mediated ring contraction and olefinmetathesis of isoxazoles is described. Hoveyda–Grubbs II catalyst was found to function as a photocatalyst for these transformations, allowing these processes to be carried out in a one-pot manner. This study offers a new entry for the application of Grubbs catalysts as efficient photocatalysts
chemoselective reaction between 5-aminoisoxazoles and α-diazocarbonyl compounds has been described. Both Wolff rearrangement and N–H insertion products can be obtained selectively by the judicious choice of reaction conditions. In the case of the Wolff rearrangementreactions, the N-isoxazole amides are accessed as the sole products under thermal conditions. On the other hand, α-amino acid derivatives
The first enantioselective dearomative [3+2] annulation of 5-amino-isoxazoles with quinonemonoimines was realized using a chiralphosphoricacid as catalyst. Various novel (bridged) isoxazoline fused dihydrobenzofurans bearing two continuous quaternary stereocenters were achieved in moderate to good yields (up to 94%) with moderate to good enantioselectivities (up to 98% ee). The absolute configurations