Efficient Transamination under Mild Conditions:  Preparation of Primary Amine Derivatives from Carbonyl Compounds via Imine Isomerization with Catalytic Amounts of Potassium tert-Butoxide

1,3-Prototropic rearrangement of N -diphenylmethanimines was successfully performed with a catalytic amount of potassium tert -butoxide. This procedure can also be used with aliphatic and aromatic aldimines and was extended to the isomerization of (1 R )-camphorquinone monoimine and N -(4-methoxyphenyl)-4-phenyl-3-iminoazetidin-2-one. The isomerized imines were easily hydrolyzed and isolated as Cbz derivatives.