Triethylamine → HCID 89648585, compound

Participants

Reaction Steps

To a solution under N2 of 8-(2-benzyloxy-5-fluoro-phenyl)-3,4-dihydro-1H-isoquinoline-2-carboxylic acid benzyl ester (208 mg, 0.45 mmol, 1.0 eq.) in EtOH (10 mL), palladium on activated carbon (10 wt. %, 21 mg) was added. The flask was evacuated and refilled with H2. The black suspension was stirred at r.t. under an H2-atmosphere for 6 hours. The black suspension was filtered through Celite and the filtrate was concentrated in vacuo to give a beige foam. To an-ice cooled suspension of the residue and triethylamine (93 μL, 0.67 mmol, 1.5 eq.) in DCM (10 mL), benzyl chloroformate (67 μL, 0.45 mmol, 1.0 eq.) was added dropwise. Upon completion of the addition, the mixture was stirred at 0° C. for 1 hour and further at r.t. for 4 hours. The reaction was quenched with 1M aq. citric acid soln. (10 mL). The layers were separated. The aq. phase was extracted with DCM (3×10 mL). The comb. org. phases were dried over Na2SO4 and concentrated in vacuo. The residue was dissolved in THF (10 mL) and 1M aq. NaOH (2 mL) was added. The mixture was stirred at r.t. for 64 hours. The org. solvent was removed in vacuo and the aq. layer was acidified with 2N aq. HCl. The aq. layer was extracted with DCM (3×10 mL). The comb. org. phases were dried over MgSO4 and concentrated in vacuo. The residue was purified by CC (SiO2, Hept/AcOEt 7:3) to give the title compound as a white foam.

Provenance & Evidence