Rearrangement of 1-Phenylbutane-1,3-diamines via an Azetidinium Cation Intermediate

Treatment of 4-amino-4-phenyl-butan-2-ol with mesyl chloride, followed by displacement with amine nucleophiles resulted in a 1,3 rearrangement via an azetidinium cation intermediate. This rearrangement has been proven to proceed via a double inversion of stereocentres at positions 1 and 3.