Boron trifluoride etherate → 7-(4-Fluorobenzyl)-9-hydroxy-5-methoxy-6-methyl-6,7-dihydropyrrolo[3,4-g]quinolin-8-one

Participants

Reaction Steps

To a solution of 16 (52 mg, 0.099 mmol) in 1.4 mL of dry CH2Cl2 under a N2 atmosphere, was added BF3.OEt2 (49 μL, 0.397 mmol) followed by triethylsilane (63 μL, 0.397 mmol). The solution was allowed to stir at ambient temperature for 1 day when LCMS indicated a clean conversion of starting materials to the desired product. The reaction was worked up by removing the solvent and dissolving the residue in EtOAc. The organic layer was washed with water and the solvent removed under reduced pressure. The residue was dissolved in 1 mL of EtOAc and triturated by addition of hexanes to provide the product 18. 1H NMR (300 MHz, CDCl3) δ 1.60 (d, 3H, J=7 Hz), 3.93 (s, 3H), 4.28 (d, 1H), J=15 Hz), 4.65 (q, 1H, J=7 Hz), 5.25 (d, 1H, J=15 Hz), 7.06 (t, 2H, J=8 Hz), 7.32 (dd, 2H, J=6, 8 Hz), 7.67 (dd, 1H, J=4, 8 Hz), 8.59 (br s, 1H), 8.61 (d, 1H, J=8 Hz), 9.11 (br s, 1H); 13C NMR (75 MHz, CDCl3) δ 16.9,42.8, 54.5, 61.9, 113.9, 115.7, 116.0, 122.7, 126.6, 129.8, 129.9, 130.8, 132.1, 133.1, 136.7, 142.4, 147.8, 148.3, 162.3 (d, J=245 Hz), 168.1; 19F NMR (282.6 MHz, CDCl3) δ 62.5; EI MS (m/z) 353.5 [MH+], 385.4 [M+Na].

Provenance & Evidence