No abstract

The concept of C-derivatization of amino acids via ß-and -chloro amino acids, obtained by selective free-radical chlorination in strong acid solution, is now extended to the -chlorination of an amino acid and in turn to the first synthesis of the optically active isomers of 3-methylproline. The exceedingly convenient synthesis does not affect the two asymmetric centers of the isoleucines employed as starting material; therefore it delivers the isomeric 3-methylprolines in optically pure form directly, without resolution. Moreover it concurrently establishes the absolute configuration of each of the four isomers. The J¡,¡ proton coupling values of the cis-trans isomers are practically identical.(10) Authors thank Mr. R. H. Redfield of these laboratories for performing several amino acid analyses.(11)

No abstract

No abstract

Photofluorination with Fluoroxytrifluoromethane, a General Method for the Synthesis of Organic Fluorine Compounds. Direct Fluorination of Bioactive Molecules