Synthesis of Enantiopure 3-Substituted Pyrroline <i>N</i>-Oxides by Highly Regioselective Oxidation of the Parent Hydroxylamines: A Mechanistic Rationale
The syntheses of four new, differently O-substituted 3-hydroxypyrroline N-oxides and the first 3-amino analogue have been performed by the use of a strategy involving double nucleophilicdisplacement of the corresponding dimesylates by hydroxylamine and oxidation of the resulting 1-hydroxypyrrolidines. The regioselectivity data of the oxidation reactions nicely confirm the mechanistic hypothesis, which