1-Ethynylnaphthalene → 12-(4-Naphthalen-1-yl-[1,2,3]triazol-1-yl)dodecyl 2,3,4,6-tetra-O-acetyl-alpha-D-mannopyranosyl-(1->3)-2,4,6-tri-O-acetyl-alpha-D-mannopyranosyl-(1->3)-2,4,6-tri-O-acetyl-alpha-D-mannopyranosyl-(1->3)-2,4,6-tri-O-acetyl-alpha-D-mannopyranosyl-(1->2)-3,4,6-tri-O-acetyl-alpha-D-mannopyranoside

Participants

Reaction Steps

In a 1 mL HPLC sample vial was loaded the azide 5 (86 mg, 50.3 μmol), t-butanol (100 μL, 0.4 M), 1-ethynylnaphthalene (83 μmol, 2 eq), copper sulfate solution (0.3 M in water, 14 μL, 4.2 μmol, 10 mol %) and sodium ascorbate solution (1 M in water, 12.4 μL, 12.4 μmol, 30 mol %) in that order. The mixture was stirred at room temperature for 11 days. The mixture was then evaporated onto silica gel and purified by flash column chromatography (1×18 cm, gradient elution with hexane-ethyl acetate 6:1, 4:1, 2:1, 1:1, 1:2 to 1:3) to give the naphthyltriazole 9 as a colourless gum (24.2 mg, 26%). 1H NMR (CDCl3, 400 MHz) δ 8.38-8.33 (m, 1H), 7.92-7.86 (m, 2H), 7.80 (s, 1H, triazole-CH), 7.72 (dd, 1H, J=7.3, 1.5), 7.54-7.48 (m, 3H), 5.31-5.15 (m, 8H), 5.03-4.87 (m, 8H), 4.47 (t, 2H, J=7.3, N—CH2), 4.30-3.77 (m, 19H), 3.64 (dt, 1H, J=9.7, 6.8, OCH2), 3.40 (dt, 1H, J=9.7, 6.8, OCH2), 2.17, 2.16, 2.16, 2.13, 2.12, 2.11, 2.11, 2.10, 2.09, 2.07, 2.06, 2.05, 2.02, 2.00, 1.97, 1.57 (15 s, each 3H, except 2.100 (6H), 16×Ac), 2.07-1.95 (m, overlapped with Ac singlets, 2H, CH2), 1.57 (m, 1H, CH2), 1.42-1.23 (m, 16H, 8×CH2).

Provenance & Evidence