2.2 Synthesis procedure
2.2.1 Compound 2
A mixture of 1 (4.22 g, 20.0 mmol), iron powder (3.35 g, 60.0 mmol, 3.0 equiv.) and ammonia chloride (2.14 g, 40.0 mmol, 2.0 equiv.) in aqueous ethanol (140 mL of alcohol and 40 mL of water) was refluxed in argon atmosphere. After complete transformation of the initial compound (about 5 h) upon inspection by TLC, the reaction mixture was treated with 70 mL of aqueous saturated sodium bicarbonate and filtered. After removing the ethanol from the filtrate obtained under reduced pressure, the resultant mixture was filtered. The solid obtained was then washed with water (3 × 30 mL) and dried in vacuum atmosphere at 50 °C. The crude product was used without further purification for the next step. A solution of the crude product, bromobutane (13.7 g, 100 mmol) and sodium tert-butoxide (9.6 g 100 mmol) in DMF (50 ml) for 8 h, and then poured into distilled water (250 mL). ethyl acetate (3 × 50 mL) was used to extract the product. The extracts were combined, washed with saturated NaCl solution, dried over anhydrous magnesium sulfate. After removal of the solvents, the product was purified by column chromatography and obtained as a syrup (6.01 g, yield: 74%). 1H NMR (400 MHz, CDCl3) δ 7.83 (dd, J = 7.9, 3.0 Hz, 2H), 7.55 (dd, J = 17.7, 7.4 Hz, 2H), 7.43 (t, J = 7.4 Hz, 1H), 6.96 (d, J = 11.9 Hz, 2H), 3.69–3.59 (m, 4H), 2.34–2.19 (m, 4H), 1.99–1.87 (m, 4H), 1.68 (dd, J = 14.9, 7.4 Hz, 4H), 1.43 (dd, J = 14.7, 7.3 Hz, 4H), 1.27 (t, J = 7.4 Hz, 6H), 1.03 (dd, J = 16.6, 9.1 Hz, 10H). 13C NMR (101 MHz, CDCl3) δ 152.41, 149.93, 148.42, 142.33, 129.80, 126.85, 124.96, 122.66, 120.66, 118.29, 111.29, 106.92, 54.92, 51.55, 40.89, 29.91, 26.28, 23.47, 20.74, 14.34, 14.12. ESI–MS (C29H43N): calcd: 405.34; found: [M + 1]+, 406.34.
2.2.2 Compound 3
To a solution of compound 2 (5.0 g, 12.3 mmol) in anhydrous chloroform (50 mL) at ambient temperature was successively added anhydrous DMF (1.0 mL, 12.3 mmol) and POCl3 (1.7 mL, 18.5 mmol), and the mixture was refluxed during one night. After hydrolysis for 2 h under vigorous stirring at ambient temperature using an aqueous solution of sodium acetate 2 M (400 mL), the product has been extracted using CH2Cl2. When the solvent was removed, the crude product has been purified by chromatography to receive a yellow oil (3.3, 62.1% yield).
1H NMR (400 MHz, CDCl3) δ 9.87 (s, 1H), 7.70 (s, 1H), 7.65 (d, J = 7.8 Hz, 1H), 7.51–7.45 (m, 2H), 6.54 (d, J = 8.6 Hz, 1H), 6.49 (s, 1H), 3.30–3.22 (m, 4H), 1.93–1.78 (m, 4H), 1.57–1.49 (m, 4H), 1.29 (dd, J = 14.9, 7.4 Hz, 4H), 0.99 (dd, J = 14.6, 7.3 Hz, 4H), 0.87 (t, J = 7.4 Hz, 6H), 0.62–0.54 (m, 10H). 13C NMR (101 MHz, CDCl3) δ 192.10, 154.28, 150.39, 149.42, 148.96, 133.28, 131.25, 127.32, 122.43, 122.03, 117.78, 111.05, 105.81, 54.73, 51.11, 40.30, 29.54, 25.94, 23.05, 20.40, 14.05, 13.81. ESI–MS (C30H43NO): calcd: 433.33; found: [M + 1]+, 434.34, [M + 23]+, 456.32.
2.2.3 Compound A
A solution of compound 3 (1.0 g, 2.3 mmol) and TCF acceptor (0.75 g, 3.7 mmol) in ethanol (20 mL) allows to stir at 70 °C during 3 h and after removal of the solvent under reduced pressure, the crude product has been additionally purified by silica chromatography to obtain A as a purple solid in 56.9% yield (0.86 g, 1.4 mmol) 1H NMR (400 MHz, CDCl3) δ 7.70 (d, J = 16.2 Hz, 1H), 7.56 (d, J = 6.5 Hz, 3H), 7.49 (s, 1H), 7.02 (d, J = 16.2 Hz, 1H), 6.65 (d, J = 8.6 Hz, 1H), 6.57 (d, J = 9.4 Hz, 1H), 3.41–3.34 (m, 4H), 2.02–1.90 (m, 4H), 1.83 (s, 6H), 1.63 (dt, J = 15.0, 7.6 Hz, 4H), 1.40 (dd, J = 15.0, 7.5 Hz, 4H), 1.12 (dd, J = 13.9, 6.6 Hz, 4H), 0.99 (t, J = 7.3 Hz, 6H), 0.71 (t, J = 7.3 Hz, 6H), 0.67–0.59 (m, 4H). 13C NMR (101 MHz, CDCl3) δ 175.98, 174.25, 154.62, 151.30, 149.90, 149.12, 148.77, 131.01, 130.48, 130.26, 128.95, 127.41, 122.81, 122.37, 118.73, 112.34, 111.94, 111.35, 105.71, 97.39, 97.00, 54.96, 51.23, 40.39, 29.63, 26.88, 26.02, 23.10, 20.47, 14.13, 13.93. ESI–MS (C41H50N4O): calcd: 614.40; found: [M + 1]+, 615.40, [M + 23]+, 637.38.
2.2.4 Compound B
A solution of compound 3 (0.5 g, 1.1 mmol) and CF3-Ph-TCF acceptor (0.38 g, 1.1 mmol) in ethanol (20 mL) was stired at 70 °C for 3 h, then after removal of the solvent under reduced pressure, the crude product was purified by silica chromatography to recive B as a green solid in 78% yield (0.65 g, 0.9 mmol)
1H NMR (400 MHz, CDCl3) δ 7.71 (d, J = 15.8 Hz, 1H), 7.48 (s, 6H), 7.41 (d, J = 7.9 Hz,1H), 7.31 (s, 2H), 6.94 (d, J = 15.8 Hz, 1H), 6.57 (d, J = 8.5 Hz, 1H), 6.46 (s, 1H), 3.30 (t, J = 7.1 Hz, 4H), 1.85 (d, J = 8.5 Hz, 4H), 1.60–1.50 (m, 4H), 1.32 (dd, J = 14.6, 7.2 Hz, 4H), 1.03 (d, J = 6.5 Hz, 4H), 0.91 (t, J = 7.2 Hz, 6H), 0.62 (t, J = 7.1 Hz, 6H), 0.54 (d, J = 6.3 Hz, 4H).
13C NMR (101 MHz, CDCl3) δ 175.47, 163.52, 155.28, 152.17, 151.39, 150.29, 149.93, 131.73, 131.29, 130.50, 129.95, 129.78, 127.33, 127.05, 123.60, 122.82, 118.79, 111.87, 111.53, 111.02, 110.87, 110.60, 105.63, 98.10, 96.96, 96.64, 54.93, 51.26, 40.24, 29.66, 26.01, 23.06, 20.47, 14.12, 13.90. ESI–MS (C46H49F3N4O): calcd: 730.39; found: [M + 1]+, 731.39, [M + 23]+, 785.40.