反应详情

Add sodium borohydride (2.0 g) to a suspension of the dihydroisoquinoline from step B (4.75 g) in ethanol (175 mL) and stir the mixture for 2 h. Concentrate to a residue, treat with water and heat on a steam bath for 0.75 h. Cool the mixture to room temperature, extract with ether and concentrate the ethereal extract to a residue. Dissolve the residue in ethyl acetate, treat with 1.7 g of maleic acid and recrystallize the resulting salt from ethanol/ethyl acetate to give the title compound as the maleate salt (4.05 g). Elemental analysis: calc. for C19H22ClNO2, C=63.9%, H=6.03%, N=3.25%; found, C=63.91, H=5.99, N=3.22.

1. concentrationConcentrate to a residue
2. additiontreat with water
3. temperatureheat on a steam bath for 0.75 h
4. extractionextract with ether
5. concentrationconcentrate the
6. extractionethereal extract to a residue
7. dissolutionDissolve the residue in ethyl acetate
8. additiontreat with 1.7 g of maleic acid
9. customrecrystallize the resulting salt from ethanol/ethyl acetate