Processes for the preparation of N-substituted phthalimides

A process for preparing a compound of Formula I:

• wherein:
• R is hydrogen, C1-2 alkyl, halogen, or C1-2 alkoxy;
• R1 is hydrogen, C1-6 alkyl, C2-6 alkenyl, or C2-6 alkynyl;
• and
• R2 is C1-6 alkyl, C2-6 alkenyl, or C2-6 alkynyl;
• comprising a) reacting a compound of Formula II:
• wherein R is as defined above, with a compound of Formula III:
• wherein R1 and R2 are as defined above,
• in the presence of a diazodicarboxylate having Formula IV:
• wherein each R3 is, independently, C1-6 alkyl;
• and in the presence of a triarylphosphine of Formula V:
• P(Ar)3 V
• wherein each Ar is phenyl optionally substituted with 1-3 substituents independently selected from CH3, OCH3 and halogen;
• and in the presence of a solvent having Formula VI:
• Ar′ VI
• wherein Ar′ is phenyl optionally substituted with 1, 2 or 3 methyl groups;
• to form said compound of Formula I;
• and
• b) precipitating said compound of Formula I from the reaction mixture by adding one or more alcohols to the reaction mixture, after said reacting of step a).