Enantioselective Michael additions of aldehydes to nitroalkenes catalyzed with ionically tagged organocatalyst
作者:Radovan Šebesta、Attila Latika
DOI:10.2478/s11532-013-0391-4
日期:2014.3.1
Enantioselective organocatalytic Michaeladditions affords useful building blocks for many biologically and medicinally relevant compounds. Ionically-tagged diphenylprolinol silyl ether efficiently catalyzes several Michaeladditions of aldehydes to nitroalkenes in ionicliquids. The Michaeladditions work well in ionicliquids; yields up to 95% and enantioselectivities up to 95% ee were achieved.
Enantioselective<i>Michael</i>Addition of the 2-(1-Ethylpropoxy)acetaldehyde to<i>N</i>-[(1<i>Z</i>)-2-Nitroethenyl]acetamide - Optimization of the Key Step in the Organocatalytic Oseltamivir Synthesis
OrganocatalyticMichaeladdition of alkoxyacetaldehyde 1 to N‐protected 2‐nitroethene‐1‐amine 2 (Scheme 2) is a keystep in the synthesis of an important antiviral agent, oseltamivir. Screening of a large array of structurally diverse acids as potential promoters led to the identification of several useful acidic additives for this reaction (Tables 1–4). Also other reaction parameters were investigated
Optimization of stereoselective Michael addition of 2-(pentan-3-yloxy)acetaldehyde to N-[(Z)-2-nitroethenyl]acetamide with the aid of design of experiments
Stereoselective Michael addition of 2-(pentan-3-yloxy)acetaldehyde to N-[(Z)-2-nitroethenyl]acetamide is a key step in the organocatalytic synthesis of oseltamivir, active ingredient in the anti-influenza drug Tamiflu. Several important reaction parameters were analyzed by the help of design of experiments and optimum reaction conditions were found. These conditions led to improvements of the reaction outcomes.