- Synthesis of (1S)-1-amino-2,2-dimethylcyclopropane-1-carboxylic acid via PLE mediated hydrolysis of bis(2,2,2-trifluoroethyl) 2,2-dimethylcyclopropane-1,1-dicarboxylate
-
Hydrolysis of bis(2,2,2-trifluoroethyl) 2,2-dimethylcyclopropane-1,1-dicarboxylate with pig liver esterase afforded (1R)-2,2-dimethyl-1-(2,2,2-trifluoroethoxycarbonyl)-cyclopropane-1-carboxylic acid in high enantiomeric excess. This compound was rearranged to (1S)-2,2,2-trifluoroethyl-2,2-dimethyl-1-[(N-ethoxycarbonyl)amino]- cyclopropane-1-carboxylate via a Curtius type reaction with DPPA. Final alkaline hydrolysis gave (1S)-1-amino-2,2-dimethylcyclopropane-1-carboxylic acid.
- Salgado,Huybrechts,Eeckhaut,Van der Eycken,Szakonyi,Fül?p,Tkachev,De Kimpe
-
-
Read Online
- Synthesis of (R)- and (S)-2,3-Methanovaline from (2S)-N-Benzoyl-2-tert-butyl-4-methylene-1,3-oxazolidin-5-one
-
The reaction of (2S)-N-benzoyl-2-tert-butyl-4-methylene-1,3-oxazolidin-5-one (9) with isopropylidenetriphenylphosphorane at room temperature gives the corresponding cis and trans spirocyclopropane derivatives 10 in ca. 1:1 ratio.After separation of both diastereomers, by recrystallization and flasch chromatography, and further acid hydrolysis, enantiomerically pure (R)- and (S)-2,3-methanovaline 11 are obtained.
- Chinchilla, Rafael,Najera, Carmen,Garcia-Granda, Santiago,Menendez-Velazquez, Amador
-
p. 5799 - 5802
(2007/10/02)
-