HCID 57733272, compound → HCID 67132488, compound

Participants

Reaction Steps

A suspension of 3-methyl-8-nitro-1-oxo-2-phenyl-1,2-dihydro-isoquinoline-4-carboxylic acid methyl ester (320 mg, 0.95 mmol) and Zn (898 mg, 13.8 mmol) in THF (4.5 ml) and 2M aq. HCl (4.5 ml) was stirred for 10 min, filtered and partitioned between ethyl acetate (3×150 ml) and sat. aq. NaHCO3 (100 ml). The combined organic solution was dried (MgSO4) and evaporated to give 8-amino-3-methyl-1-oxo-2-phenyl-1,2-dihydro-isoquinoline-4-carboxylic acid methyl ester as a dark oil (200 mg, 0.645 mmol, 69% yield. LC-MS (m/z) 309.4 (MH+); tR=1.2. It was dissolved in conc. aq. HCl (0.4 ml) and H2O (3.25 ml). To the obtained solution NaNO2 (46.3 mg, 0.645 mmol, in 0.12 ml H2O) was added dropwise at 0° C. After 15 min it was neutralized (pH=6-7) with sat. aq. NaHCO3 to give diazonium salt solution. To a solution of KCN (202 mg, 3 mmol) in water (0.4 ml) solution of CuSO4×5H2O (197 mg, 0.774 mmol) in water (0.8 ml) was added dropwise at 0° C. After addition completion benzene (2 ml) was added and the mixture was warmed to +60° C. To this mixture diazonium salt solution was added dropwise during 15 min then kept at 70° C. for 85 min. It was allowed to cool to r.t., diluted with ethyl acetate (10 ml) and filtered via plug of cellite. The organic layer was washed with brine (10 ml), dried (MgSO4) and evaporated to give 97.9 mg of the title compound (48% yield). LC-MS (m/z) 319.2 (MH+); tR=1.15.

Provenance & Evidence