1,2,3,4-Tetrahydroisoquinoline → 3,4-Dihydroisoquinoline

Participants

Reaction Steps

N-Bromosuccinimide (9.89 g, 55.0 mmol, 1.1 eq.) was added cautiously and portionwise over 20 min to a solution of 1,2,3,4-tetrahydroisoquinoline (6.34 mL, 50.0 mmol, 1.0 eq.) in DCM (130 mL) at r.t. The mixture was stirred at r.t. for 1.5 hour. 30% aq. NaOH (35 mL) was added and the mixture was stirred at r.t. for 2 hours. The organic layer was separated and washed with water (1×70 mL). The product was extracted with 10% aq. HCl (2×80 mL). The combined acidic extracts were washed with DCM (1×80 mL) and basified with 25% NH3. The resulting mixture was extracted with DCM (2×80 mL). The comb. org. extracts were dried over MgSO4, filtered and concentrated in vacuo to yield the 3,4-dihydroisoquinoline as an orange oil. The product was used without further purification.

Provenance & Evidence