反应详情

A solution of (±)-(cis)-[(3-azido-2-oxo-4-azetidinyl)methoxy]acetic acid (0.880 g, 4.42 mmole) was treated with a solution of diphenyl diazomethane (858 mg, 4.42 mmole) in acetone (12 ml). The reaction was stirred at room temperature for nineteen hours and then combined with another run (621 mg acid, 3.12 mmole). The solvent was removed in vacuo and ethyl acetate was added and evaporated. The residue was dissolved in ethyl acetate (70 ml), dried (sodium sulfate), filtered, and concentrated to 2.6 g of a heavy yellow-red oil. The crude product was chromatographed on silica gel (230-400 mesh, 100 g) with 50% hexane-ethyl acetate. Concentration of the appropriate fractions and removal of solvents produced a heavy oil which was triturated with ether to produce a white solid which was filtered and dried to yield 1.34 g of the title compound. An additional 463 mg was obtained from the mother liquor. The total yield was 1.804 g.

1. customThe solvent was removed in vacuo and ethyl acetate
2. additionwas added
3. customevaporated
4. dissolutionThe residue was dissolved in ethyl acetate (70 ml)
5. dry with materialdried (sodium sulfate)
6. filtrationfiltered
7. concentrationconcentrated to 2.6 g of a heavy yellow-red oil
8. customThe crude product was chromatographed on silica gel (230-400 mesh, 100 g) with 50% hexane-ethyl acetate
9. customConcentration of the appropriate fractions and removal of solvents
10. customproduced a heavy oil which
11. customwas triturated with ether
12. customto produce a white solid which
13. filtrationwas filtered
14. customdried