Synthesis of Isoindoles from Intramolecular Condensation of Benzyl Azides with α‑Aryldiazoesters

Rh-catalyzed intramolecular condensation
of the benzyl azides with
α-aryldiazoesters was explored. The reaction proceeded through
the nucleophilic attack of the organic azide onto a rhodium carbenoid,
while releasing nitrogen gas, affording the α-imino esters as
the primary product. Tautomerization of the imino esters efficiently
gave 13 desired isoindoles with good to excellent yields.