反应详情

A suspension of cis-1-(benzyloxycarbonyldiethylphosphono)methyl-3-azido-4-(3-ethylenedioxybutyl)-2-azetidinone (0.10 g.) in 10% aqueous sulfuric acid (8 ml.) and glacial acetic acid (1 ml.) is heated with stirring at 50° for 2 hrs. The mixture is cooled to room temperature and extracted with methylene chloride (3×15 ml.) The combined extracts are washed with brine (2×10 ml.), dried with magnesium sulfate, filtered, and evaporated in vacuo to yield 60% of cis-1-(benzyloxycarbonyldiethylphosphono)methyl-3-azido-4-(3-oxobutyl)-2-azetidinone as a light brown oil. NMR (CDCl3) δ: 1.27 (m, O--CH2 --CH3); 2.13 (s, CH3); 4.12 (m, O--CH2CH3 and H4); 4.72 (d, J=5.5 Hz, H3); 5.23 (s, OCH2 φ); 7.35 (φ). IR (film) μ: 4.70 (N3); 5.61 (β-lactam); 5.70 (ester); 5.82 (C= O) M+ (Calc. 466) Found 466.

1. temperatureis heated
2. extractionextracted with methylene chloride (3×15 ml.) The combined extracts
3. washare washed with brine (2×10 ml.)
4. dry with materialdried with magnesium sulfate
5. filtrationfiltered
6. customevaporated in vacuo