4.3 Synthesis
Synthesis of (S)-2,2'-bis(methoxymethoxy)-3,3'-bis(hydroxymethyl)-1,1'-binaphthol (S-3) (S)-2,2'-bis(methoxymethoxy)-3,3'-diformyl-1,1'-binaphthol (S-2)(5.2 g, 12.1 mmol) was disolved in CH3OH:THF = 2:3 solution (20 ml) under ice-cooling. NaBH4 (1.82 g, 47.9 mmol) was added in little portions and stirred at room temperature for 12 h. After quenched by saturated salt water, the mixture was extracted with ethyl acetate. The combined organic phase was then washed with brine and dried over anhydrous magnesium sulfate. After removal the solvent, 5.1 g pale yellow oil was obtained (97% yield). 1H NMR (400 MHz, CDCl3) δ 8.04 (s, 1H), 7.91 (d, J = 8.2 Hz, 1H), 7.43 (t, J = 7.4 Hz, 1H), 7.32–7.23 (m, 1H), 7.17 (d, J = 8.5 Hz, 1H), 4.93 (dd, J = 51.5, 12.7 Hz, 2H), 4.48 (dd, J = 14.3, 6.1 Hz, 2H), 3.17 (s, 3H). 13C NMR (100 MHz, CDCl3) δ 153.1, 134.7, 133.9, 131.1, 129.7, 128.3, 126.9, 125.93, 125.5, 125.3 99.4, 61.9, 57.2 (ppm).
Synthesis of (S)-2,2'-bis(methoxymethoxy)-3,3'-bis(O-Propargyloxymethyl)-1,1'-binaphthol (S-4)
A stirred solution of S-3 (2.5 g,5.75 mmol) dissolved in anhydrous THF (40 mL) at 0°C under nitrogen, and NaH (0.6 g, 25.0 mmol) was added in little portions. 3-Bromo-1-propyne (2.5 mL, 29 mmol) were added dropwise. The reaction was stirred overnight, and warmed to room temperature. Quenched with water slowly. Extracted with ethyl acetate, washed with brine and dried over Na2SO4. The crude product was purified by a silica column using 1:1 hexane: EtOAc to afford compound as a yellow oil (2.64 g, 90% yield).1H NMR (400 MHz, CDCl3) δ 8.26 (s, 1H), 8.07 (d, J = 8.1 Hz, 1H), 7.58 (t, J = 7.3 Hz, 1H), 7.43 (t, J = 7.5 Hz, 1H), 7.37 (d, J = 8.4 Hz, 1H), 5.13 (s, 2H), 4.79 (d, J = 5.7 Hz, 1H), 4.68 (d, J = 5.7 Hz, 1H), 4.54 (d, J = 1.9 Hz, 2H), 3.02 (s, 3H), 2.68 (s, 1H). 13C NMR (100 MHz, CDCl3) δ 152.1, 133.8, 131.1, 130.7, 129.1, 128.0, 126.5, 126.1, 125.3, 99.4, 79.7, 74.8, 67.7, 57.9, 56.6(ppm).
Synthesis of (S)-3,3'-bis(O-Propargyloxymethyl)-1,1'-binaphthol. (S-5)
A mixture of S-4 (1.0 g, 2.0 mmol), methanol (40 mL) and THF (60 ml) and con. HCl (15 mL) were stirred at at room temperature for 3 h. After quenched the reaction by H2O slowly, the resulting residue was extracted with ethyl acetate, washed with brine and dried over Na2SO4. After filtered, evaporation of the solvent to obtain the desired product (0.7g, 85%) as a brown oil. 1H NMR (400 MHz, CDCl3) δ 7.92 (s, 1H), 7.83 (d, J = 8.0 Hz, 1H), 7.30 (t, J = 7.3 Hz, 1H), 7.21 (d, J = 6.5 Hz, 2H), 7.07 (d, J = 8.4 Hz, 1H), 5.95 (s, 1H), 4.92 (s, 2H), 4.30 (s, 2H), 2.46 (s, 1H). 13C NMR (100 MHz, CDCl3) δ 150.0, 132.4, 128.4, 127.9, 127.2, 126.1, 124.4, 123.4, 123.0, 112.1, 78.2, 74.2, 67.6, 56.8 (ppm).
Synthesis of ( S, β-D )-1. 2,3,4,6-Tetra-O-acetyl-beta-D-glucopyranosyl azide (1.09 g,2.92 mmol)and S-5 (0.41 g༌0.97 mmol) were added to a stirred 42 mL THF at 273K under a argon atmosphere. Sodium ascorbate༈0.43 g༌2.14 mmol༉, CuSO4.5H2O༈0.25 g༌0.98 mmol༉and H2O (8 mL) were added in turn slowly. The mixture was stirred room temperature for 12 h under argon. After the reaction finished, the mixture was poured into 100 mL ice-water, extracted with EtOAc, washed with brine and dried over anhydrous MgSO4. The combined filter concentrated, the crude product was purified directly by column chromatography on silica by using petroleum ether: EtOAc = 1: 1 as the eluent to provide a pale solid (S, β-D)-1 (0.63 g, 46%). [α]D25 = -29.0 (c = 1 CH3CN). Mp 129–131°C. IR (KBr) 3435, 3151, 2960, 2125, 1754, 1627, 1369, 1227, 1106, 1030, 803 cm− 1; 1H NMR (400 MHz, CDCl3) δ 7.93 (s, 1H), 7.90–7.79 (m, 2H), 7.31 (t, J = 7.2 Hz, 1H), 7.22 (t, J = 7.4 Hz, 1H), 7.08 (d, J = 8.1 Hz, 1H), 5.86 (d, J = 7.6 Hz, 1H), 5.50–5.34 (m, 2H), 5.23 (t, J = 7.9 Hz, 1H), 4.90 (s, 2H), 4.83 (s, 2H), 4.26 (d, J = 12.4 Hz, 1H), 4.11 (d, J = 12.4 Hz, 1H), 3.98 (d, J = 7.3 Hz, 1H), 2.03 (d, J = 17.4 Hz, 10H), 1.79 (s, 2H). 13C NMR (100 MHz, CDCl3) δ 170.4, 169.8, 169.3, 168.9, 151.3, 145.5, 133.6, 129.4, 128.9, 128.2, 126.9, 125.8, 124.5, 123.8, 121.2, 113.3, 85.7, 75.1, 72.6, 70.4, 69.2 67.8, 63.5, 61.5, 20.7–20.3, 20.0 (ppm). MS (ESI−): calcd for [C56H60N6O22-H]− 1168.3; found 1167.2.