53% |
With silver hexafluoroantimonate; iodosylbenzene; sodium carbonate; (S,S)-2,2'-isopropylidenebis(4-phenyl-2-oxazoline); copper(l) chloride; In benzene; at 20℃; for 3h;Inert atmosphere; Molecular sieve; |
General procedure: CuCl (1.0 mg, 0.01 mmol, 2 mol %), AgSbF6 (4.1 mg, 0.012 mmol, 2.4 mol %), and bis(oxazoline) 2 (0.012 mmol, 2.4 mol %) were weighed in the glove box and charged together in a flask. After removal from glove box, the vial was capped and benzene (5 mL) was added. The solution was stirred for 1 h at room temperature, after which styrene (2.5 mmol, 5.0 equiv) was added to the catalyst solution. In a separate vial, PhIO (121 mg, 0.55 mmol, 1.10 equiv), Na2CO3 (122 mg, 1.15 mmol, 2.30 equiv), and molecular sieves (approx. 100 mg) were charged in a vial and purged under argon for 10 min. The solids were then quickly transferred to the catalyst solution, followed by <strong>[2483-57-0]methyl nitroacetate</strong> (1) (59.5 mg, 0.50 mmol). The solution was stirred at room temperature for 3 h. The reaction was quenched with water (5 mL) and organic layer was extracted with ethyl acetate (2×10 mL). The combined organic layers were dried over Na2SO4, filtered, and concentrated under reduced pressure. The crude oil residue was purified by flash column chromatography to give the pure 1-nitrocyclopropyl carboxylate 3. |