A three-ste
p mechanism involving the formation and rearrangement of an intermediate with indoline-azetidine s
pirocyclic core structure wasshown by DFT com
putations to account for the electro
philic cyclization of try
pto
phan derivatives to hexahydro
pyrrolo[2,3-
b]indoles. Thecorres
ponding 3a-bromo derivatives have been obtained in high yields and synthetically useful
exo/
endo ratios.