1,2-Dichloroethane → (S)-tert-Butyl 3-formyl-3,4-dihydroisoquinoline-2(1H)-carboxylate

Participants

Reaction Conditions

Reaction Steps

To a round-bottomed flask equipped with stirring was added Boc-L-Tic-OH (Bachem) (1 g, 3.6 mmol) and CH2Cl2 (20 mL), followed by TEA (0.5 mL, 3.6 mmol) and N,O-dimethylhydroxylamine hydrochloride. The reaction mixture was cooled to 0° C., EDC (690 mg, 3.6 mmol) and HOBT (550 mg, 3.6 mmol) were added, and the reaction mixture was stirred at 0° C. for 1 h then at RT for 18 h. The organic layer was washed with 0.5 N HCl, satd NaHCO3, and brine. The organic layer was dried over Na2SO4, filtered and concentrated in vacuo to afford a colorless oil. Into a round bottomed flask equipped with magnetic stirring, was added the oil dissolved in Et2O (15 mL), and the flask was cooled to −78° C. LiAlH4 (1M in Et2O, Aldrich) (3.2 mL, 3.2 mmol) was added, and after 30 min the reaction was warmed to RT. The organic layer was washed with 0.5 N HCl, satd NaHCO3, and brine. After drying the organic layer over Na2SO4, it was filtered and concentrated in vacuo to afford (3S)—N-Boc-1,2,3,4-tetrahydroisoquinoline-3-carbaldehyde as a colorless oil (588 mg).

Provenance & Evidence