Trimethylsilyl triflate → 3-(2,3,4-tri-O-acetyl-alpha-L-fucopyranosyl)-1-propene
Reaction equation
C(O[C@@H:5]1[O:22][C@@H:21]([CH3:23])[C@@H:16]([O:17][C:18](=[O:20])[CH3:19])[C@@H:11]([O:12][C:13](=[O:15])[CH3:14])[C@@H:6]1[O:7][C:8](=[O:10])[CH3:9])(=O)C.[CH2:24]([Si](C)(C)C)[CH:25]=C.[Si](OS(C(F)(F)F)(=O)=O)(C)(C)[CH3:32]>C(C#N)(C)=O.C(Cl)Cl.C([O-])(O)=O.[Na+]>[C:18]([O:17][C@H:16]1[C@H:11]([O:12][C:13](=[O:15])[CH3:14])[C@H:6]([O:7][C:8](=[O:10])[CH3:9])[C@H:5]([CH3:32])[O:22][C@H:21]1[CH2:23][CH:24]=[CH2:25])(=[O:20])[CH3:19]Participants
Reactant 3
Product 1
Reagents, catalysts & solvents 3
Conditions
- Temperature
- 0 °C
Procedure
To a solution of 1,2,3,4-tetra-O-acetyl-α-L-fucopyranose (12 g, 36.1 mmol) and allyltrimethyl silane (11.48 mL, 72.2 mmol) in AcCN (60 mL) at 0° C. was added TMS-OTf (3.52 mL, 19.50 mmol). The reaction mixture was stirred at 0° C. for 18 hr and then at rt for 6 hr. The resulting red solution was diluted with CH2Cl2 (250 mL) and sat'd NaHCO3 (150 mL) was added carefully. The aqueous layer was separated and extracted with CH2Cl2 (2×50 mL). The combined organic layers were dried over Na2SO4, filtered and concentrated. The residue was purified by flash chromatography on silica gel (220 g), eluting with 15% EtOAc in hexanes to give the title compound. 1H NMR (CDCl3, 400 MHz) δ 1.16 (d, J=6.4, 3H), 2.04 (s, 3H), 2.08 (s, 3H), 2.18 (s, 3H), 2.34 (m, 1H), 2.57 (m, 1H), 4.00 (m, 1H), 4.29 (dt, J=10.4, 7.3, 1H), 5.13 (m, 2H), 5.23 (dd, J=10.0, 3.4, 1H), 5.30 (dd, J=3.4, 1.9, 1H), 5.35 (dd, J=10.0, 5.6, 1H), 5.77 (m, 1H).
Workup
- waitat rt for 6 hr
- additionwas added carefully
- customThe aqueous layer was separated
- extractionextracted with CH2Cl2 (2×50 mL)
- dry with materialThe combined organic layers were dried over Na2SO4
- filtrationfiltered
- concentrationconcentrated
- customThe residue was purified by flash chromatography on silica gel (220 g)
- washeluting with 15% EtOAc in hexanes
Sources & evidence
- ORD record
- ord-a8cb022575334804bc97c2db1b18e1a1
- Source dataset
- uspto-grants-2016_08
- Patent number
- US09427475B2
Reaction notes
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