8-Hydroxyquinoline → 6-Chloro-2,3-dihydro-1h-indole

Participants

Reaction Steps

This material was conveniently prepared on multigram scale from the cyclization of 2,4-dichlorophenethylamine in the presence of Na2 CO3 (s) (1.2 mol eq), Cu2Cl2 (0.01 mol eq) and 8-hydroxyquinoline (0.012 mol eq) in isoamyl alcohol (1 vol) at 130° C. for 5 hours. After addition of hydrazine (0.0055 vol) and 1 hour reflux, the mixture was filtered, solvent was removed in vacuo (45° C. @ ~10 mm Hg) and 6-chloro-indoline was obtained pure by vacuum distillation (95°-100° C. @ 2 mm Hg)(65-95%).

Provenance & Evidence