Racemic and Optically Active Hydantoins from Disubstituted Cyanoacetic Acids
Starting from the chiral disubstituted cyanoacetic acids 1 the racemates and some enantiomers of the 5,5-disubstituted hydantoins 6 and of the 3-methylhydantoins 7 are synthesized via the isocyanates 3.Their absolute configurations are determined.