[I:1][C:2]1[CH:11]=[CH:10][CH:9]=[C:8]2[C:3]=1[CH2:4][CH2:5][NH:6][CH:7]2[CH2:12][C:13]([O:15]CC)=O.IC1C=CC=C2C=1CCN/C/2=C\C([O:32][CH2:33][CH3:34])=O.[BH3-]C#[N:37].[Na+].C([O-])(O)=O.[Na+]>CCO.CC(O)=O>[I:1][C:2]1[CH:11]=[CH:10][CH:9]=[C:8]2[C:3]=1[CH2:4][CH2:5][N:6]1[C:33](=[O:32])[CH2:34][NH:37][C:13](=[O:15])[CH:12]=[C:7]12ethyl 2-(5-iodo-1,2,3,4-tetrahydroisoquinolin-1-yl)acetate. A solution of (Z)-ethyl 2-(5-iodo-3,4-dihydroisoquinolin-1(2H)-ylidene)acetate (40.0 g, 116 mmol) in dry EtOH (430 mL) was treated with AcOH (33 mL) and NaBH3CN (9.63 g, 146 mmol) portionwise at RT under Ar. The mixture was stirred at RT for 1.5 h, and another load of NaBH3CN (3.85 g, 58 mmol) was then added portionwise. The mixture was stirred for another 1.5 h, and then poured onto a saturated aq. solution of NaHCO3. The pH was adjusted to 8, and the mixture was then extracted with AcOEt. The combined org. layers were dried over Na2SO4, filtered and concentrated in vacuo to give the title compound (39.5 g) as an orange oil that was used as it is in the next step. UPLC-MS: MS 346.1 (M+H+); UPLC rt 0.66 min.
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