55063-97-3Relevant articles and documents
Palladium(II)-Catalyzed Asymmetric Acetalization of Alkenes
Hosokawa, Takahiro,Yamanaka, Toshio,Itotani, Motohiro,Murahashi, Shun-Ichi
, p. 6159 - 6167 (2007/10/03)
The terminal olefinic carbon of N-methaacryloyl-2-oxazolidinones is smoothly acetalized by alcohols in the presence of PdCl2 catalyst.The use of 4(S)-isopropyl-, phenyl-, and tert-butyl-2-oxazolidinones as the chiral auxiliary resulted in the formation of the corresponding (2'S)-acetals in 61, 80, and 95percent de, respectively.Reductive removal of the auxiliary with LiAlH4 followed by deacetalization produced (R)-3-hydroxy-2-methylpropanal.The enantiomer of this compound, derived from 4(R)-substituted oxazolidinones, served as a building block for synthesizing a 1β-methylcarbapenem precursor in high enantiomeric excess.In the acetalization of 3',3'-dideuteriated methacryloyl-4-isopropyloxazolidinone with MeOH, one D-atom on the terminal olefinic carbon stereoselectively migrated to the chiral center in the product acetal.On the basis of this 1,2-hydride migration and the conformational preference of the methacryloyl moiety, the reaction pathway and the mechanism of the diastereoselection are discussed.
The synthesis of deuterated methyl methacrylates
Ayrey,Wong
, p. 935 - 944,939,940,943 (2007/10/06)
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