197644-33-0Relevant academic research and scientific papers
Synthesis of highly enantio-enriched α-amino acids by carboxylation of N-(α-lithioalkyl)oxazolidinones
Jeanjean, Fabien,Fournet, Guy,Bars, Didier Le,Gore, Jacques
, p. 1297 - 1305 (2007/10/03)
N-(α-Stannylalkyl)oxazolidinones can be obtained as a mixture of diastereomers in three steps from aldehydes with yields dependent on the R group of R-CHO. They can be transformed by a tin-lithium exchange to N-(α- lithioalkyl)oxazolidinones which equilibrate rapidly to one diastereomer. These compounds give rise, after carboxylation, to the diastereopure N-(α- carboxyalkyl)oxazolidinones. Transformation of the oxazolidinone moiety to a free amino group is accomplished by a Birch-type reduction. Using this method, L-methionine, L-alanine, L-leucine and L-homocysteine were obtained in good yields and ee = 92% to 95%. The short time required for the whole sequence makes this method ideal for synthesising 1-[11C]amino acids.
Asymmetric carboxylation in the synthesis of L-methionine: A new tool for 11C chemistry
Jeanjean, Fabien,Perol, Nathalie,Gore, Jacques,Fournet, Guy
, p. 7547 - 7550 (2007/10/03)
L-methionine is obtained in good yield and high e.e. by using the carboxylation of an enantiopure α-lithio oxazolidinone prepared by tin-lithium exchange. The entire process from α-stannyl oxazolidinone takes 35-40mn, time which is compatible with the use of 11CO2 in radioactive chemistry directed to PET imaging.
