Nucleophilicaddition of organometallics to N,N-dimethyl-glyoxal-monohydrazone occurs smoothly to give the corresponding α-hydroxy hydrazones in high yields. From these compounds, polyfunctional derivatives such as protected α-hydroxy aldehydes and α-hydroxy nitriles can be easily obtained in satisfactory to good yields. The addition to a SAMP-hydrazone proceeds with low (35% d.e.) or reasonable (60%
A highly diastereoselective synthesis of trans-2-substituted cyclopentylamines via a tandem hydrozirconation/Lewis acid-mediated cyclization sequence applied to butenyl oxazolidines is described. The method allows an easy preparation of diversely substituted cyclopentylamines which appear to be useful synthetic intermediates. This was further illustrated by the syntheses of (±)-Rodocaine, (±)-trans-pentacin