Description
Phthalimides can easily be converted into primary amines, which are useful in a wide variety of laboratory and industrial applications. A new reaction has been discovered which allows for the synthesis of N-phthalimido-O-acyl-N,O-acetals from acyl phthalimides and aldehydes. These products can undergo hydrazinolysis to become useful primary amines. In addition, it is possible to combine the reaction with the synthesis of the participating acyl phthalimides, resulting in a one-pot synthesis of N-phthalimido-O-acyl-N,O-acetals from an acid chloride, phthalimide salt, and aldehyde.
Previous research showed that a metal Lewis acid and a tertiary amine were required for the reaction to take place. The optimal conditions included at least 10 mole percent LiBF4 and acetonitrile as the solvent. The reaction proceeds to 99% completion in less than 1 hour. Early mechanistic experiments show that the acyl group and phthalimide group completely dissociate to facilitate the insertion of the aldehyde.