反应详情

A solution of 930 mg. (2 mmol.) of p-methoxybenzyl 7-phthalimido-3-methyl-3-cephem-4-carboxylate in 25 ml. of THF and 8 ml. of water was cooled in an ice water bath, and 660 mg. of Na2S.9H2O were then added. The mixture was stirred for 15 min., and 10 ml. of water and 40 ml. of ethyl acetate were added. The layers were separated, and 140 mg. of a neutral material were obtained from the ethyl acetate layer. The aqueous layer was acidified to pH 4.3 with 1N H2SO4 and extracted twice with ethyl acetate. The ethyl acetate extract was washed, dried, and evaporated to give 660 mg. (68%) of the phthalamic acid as an amorphous solid, [α]D + 85.6° (MeCN); ir (CHCl3), 1781, 1740 and 1710 cm-1, nmr (CDCl3) δ 2.08 (s, 3, CH3), 3.1 and 3.43 (ABq, 2, J = 17 Hz), 3.79 (s, 3, CH3), 5.0 (d, 1, J = 4.5 Hz), 5.1 (s, 2, CH2), 5.8 (dd, 1, J = 4.5 Hz), 6.75-7.6 (m, 8).

1. customThe layers were separated
2. customof a neutral material were obtained from the ethyl acetate layer
3. extractionextracted twice with ethyl acetate
4. extractionThe ethyl acetate extract
5. washwas washed
6. customdried
7. customevaporated
8. customto give 660 mg