反应详情

Trifluoroacetic acid (8 ml.) was added to a solution of the above ester (1.387 g.) in anisole (2 ml.) at 20°. After 5 minutes the solution was concentrated under reduced pressure and the residue was dissolved in ethyl acetate. The solvent was evaporated and again the residue was dissolved in ethyl acetate. The solution was washed with water and then extracted with sodium bicarbonate solution. The combined extracts were washed with ethyl acetate, then taken to pH 1.9 with concentrated hydrochloric acid and extracted with ethyl acetate. The extract was washed with water and brine, dried and concentrated under reduced pressure to give a foam. Trituration with ether gave the title compound as a buff solid (0.50 g.), [α]D -84° (c 1, DMSO), λmax. (pH 6 buffer) 271.5 nm (ε 17,600), νmax. (Nujol) include 3250 (NH), 1780 (β-lactam), 2600+1710 (CO2H), and 1674+1548 cm.-1 (CONH), τ values (DMSO-d6) 0.24 (doublet, J 8 Hz; NH) 2.37 and 2.82 (thienyl protons) 4.12 (double doublet, J 5 and 8 Hz; C-7H), 4.76 (doublet, J 5 Hz; C-6H), 5.40 and 5.75 (2 doublets, branches of quartet, J 13 Hz; C-3 CH2), 6.13+6.40 (2 doublets, branches of quartet, J 18 Hz; C-2 CH2) and 7.29 (singlet; CH3).

1. concentrationAfter 5 minutes the solution was concentrated under reduced pressure
2. dissolutionthe residue was dissolved in ethyl acetate
3. customThe solvent was evaporated
4. dissolutionagain the residue was dissolved in ethyl acetate
5. washThe solution was washed with water
6. extractionextracted with sodium bicarbonate solution
7. washThe combined extracts were washed with ethyl acetate
8. extractionextracted with ethyl acetate
9. washThe extract was washed with water and brine
10. customdried
11. concentrationconcentrated under reduced pressure
12. customto give a foam