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42 Chapter 2 2 Phenyl 3-O-(2-naphthyl)methyl-4,6-O-di-tert-butylsilanediyl-1-thio-β-D-galacto- pyranoside (30). Bu 2 SnO (5.78 g, 23 mmol) was added to compound 29 38 (7.98 g, 19 mmol) in toluene (100 mL) and the suspension was heated under reflux for 3 h. The resul�ng clear solu�on was cooled to 90 °C and a�er the addi�on of 2-(bromomethyl)naphthalene (4.70 g, 21 mmol), tetrabutylammonium iodide (7.86 g, 21 mmol) was added por�onwise over 1 h. A�er overnight s�rring at 90 °C, the reac�on mixture was concentrated in vacuo . The obtained crude was dissolved in DCM, washed with sat. aq. NaHCO 3 , extracted with DCM (2x), washed with brine, dried (Na 2 SO 4 ) and filtered over a pad of Celite. The concentrated crude was purified by silica column chromatography using Toluene:EtOAc (1:0 to 10:1 v/v) as the eluent to afford compound 30 (5.88 g, 55 %). 1 H NMR (400 MHz, CDCl 3 ) δ 7.88 – 7.75 (4H, m, Ar-H), 7.58 – 7.52 (3H, m, Ar-H), 7.51 – 7.43 (2H, m, Ar-H), 7.34 – 7.22 (3H, m, Ar-H), 4.96 (1H, d, J = 11.9 Hz, CHH, Nap), 4.81 (1H, d, J = 11.9 Hz, CHH, Nap), 4.61 – 4.54 (2H, m, H-1, H-4), 4.23 (2H, dd, J = 12.5, 1.9 Hz, H-6), 4.06 (1H, dd, J = 9.5, 1.9 Hz, H-2), 3.41 (1H, dd, J = 9.1, 3.0 Hz, H-3), 3.35 (1H, s, H-5), 2.60 (1H, d, J = 1.9 Hz, OH, H-2), 1.08 (9H, s, t-Bu), 1.07 (9H, s, t-Bu). 13 C NMR (101 MHz, CDCl 3 ) δ 135.6, 133.60, 133.25, 133.09, 132.53, 128.85, 128.37, 127.87, 127.72, 127.67, 126.61, 126.19, 125.99, 125.85, 89.2 (C-1), 81.8 (C-3), 75.1 (C-5), 70.5 (CH 2 , Nap), 69.5 (C-4), 68.6 (C-2), 67.4 (C-6), 27.7 (3x CH 3 , t-Bu), 27.6 (3x CH 3 , t-Bu), 23.4 (C, t-Bu), 20.7 (C, t-Bu). ESI HRMS (m/z): [M + Na] + calcd for C 31 H 40 O 5 SSi, 575,2263; found 575.2260. [α] 25/589 = -10.0° (C = 0.01; CHCl 3 ). Phenyl 2-O-benzyl-3-O-(2-naphthyl)methyl-4,6-O-di-tert-butylsilanediyl-1-thio-β-D- galactopyranoside (11). A mixture of compound 30 (1.9 g, 3.4 mmol) and NaH (60 % dispersion in oil; 275 mg, 6.9 mmol) in DMF (10 mL) was s�rred at 0°C for 10 min. Benzyl bromide (612 µL, 5.2 mmol) was added dropwise and the mixture was s�rred at RT for another 30 min before quenching with AcOH in MeOH. The mixture was concentrated in vacuo , diluted with DCM and washed with 1M HCl and water. The organic phase was dried (Na 2 SO 4 ), filtered and concentrated in vacuo . Crystalliza�on from MeOH provided compound 11 (1.39 g, 63 %). 1 H NMR (400 MHz, CDCl 3 ) δ 7.86 – 7.77 (3H, m, Ar-H), 7.76 – 7.69 (1H, m, Ar-H), 7.57 – 7.50 (3H, m, Ar-H), 7.50 – 7.40 (3H, m, Ar-H), 7.38 – 7.18 (7H, m, Ar-H), 4.98 – 4.82 (4H, m, 2x CH 2 , Bn, Nap), 4.66 (1H, d, J = 9.8 Hz, H-1), 4.52 (1H, d, J = 2.7 Hz, H-4), 4.18 (2H, dd, J = 12.4, 1.9 Hz, H-6), 3.88 (3H, t, J = 9.4 Hz, H-2), 3.52 (1H, dd, J = 9.1, 3.0 Hz, H-3), 3.26 (1H, s, H-5), 1.15 (9H, s, t-Bu), 1.09 (9H, s, t-Bu). 13 C NMR (101 MHz, CDCl 3 ) δ 138.37, 135.83, 134.82, 133.21, 133.01, 132.02, 128.70, 128.41, 128.29, 128.19, 127.84, 127.69, 127.66, 127.22, 126.44, 126.07, 125.86, 88.7 (C-1), 82.6 (C-3) 77.3 (C-2), 75.9, 74.7 (C-5), 71.1, 70.1 (C-4), 67.3 (C-6), 27.7 (CH 3 , t-Bu), 27.6 (CH 3 , t-Bu), 23.4 (C, t-Bu), 20.7 (C, t-Bu). ESI HRMS (m/z): [M + Na] + calcd for C 38 H 46 O 5 SSi, 665.2733; found 665.2731. [α] 25/589 = 4.5° (C = 0.1; CHCl 3 ). O O O NapO OH Si SPh O O O NapO OBn Si SPh