反应 #6391

反应方程式

Pivaloyloxymethyl bromide

sodium iodide

iodide

sodium (6R,7R)-7-[2(2-aminothiazol-4-yl)-2-(Z)-methoxyiminoacetamido]-3-[(5RS)-2-oxotetrahydrofuran-5-yl]ceph-3-em-4-carboxylate

→

title compound

收率 59.1%

Pivaloyloxymethyl (6R,7R)-7-[2-(2-aminothiazol-4-yl)-2-(Z)-methoxyiminoacetamido]-3-[(5RS)-2-oxotetrahydrofuran-5-yl]ceph-3-em-4-carboxylate

收率 59.1%

溶剂

acetone

ethyl acetate

toluene

N-methylpyrrolidone

反应条件

后处理

1. 1
   过滤filtered
2. 2
   其他evaporated in vacuo
3. 3
   洗涤washed twice with water
4. 4
   干燥with brine, dried
5. 5
   浓缩concentrated
6. 6
   其他flash chromatographed on silica gel eluting with 80,90,100% ethyl acetate in hexane

实验过程

Pivaloyloxymethyl bromide (0.10 g, ca. 0.5 mmol) and sodium iodide (0.1 g) in acetone (1 ml) were stirred for 0.25 h, filtered and evaporated in vacuo. The iodide in toluene (0.5 ml) was added to sodium (6R,7R)-7-[2(2-aminothiazol-4-yl)-2-(Z)-methoxyiminoacetamido]-3-[(5RS)-2-oxotetrahydrofuran-5-yl]ceph-3-em-4-carboxylate (0.124 g, 0.25 mmol) in N-methylpyrrolidone (2 ml) and stirred for 0.5 h. The reaction mixture was diluted with ethyl acetate, washed twice with water, and with brine, dried, concentrated and flash chromatographed on silica gel eluting with 80,90,100% ethyl acetate in hexane to give the title compound (86 mg, 59%), νmax (CH2Cl2) 1780, 1753, 1735, 1682, 1532, 1374, 1121, 1046 cm-1 ; δH (250 MHz, CDCl3) (9H, s), 1.9-2.2 (1H, m), 2.4-2.8 (3H, m), 3.34 and 3.64, 3.48 and 3.59 (together 2H, 2ABq, J 18.9, 18.4 Hz), 4.08 (3H, s), 5.10, 5.11 (together 1H, 2d, J 4.9 Hz), 5.35 (2H, bs), 5.5-5.95 (3H, m), 6.00, 6.10 (together 1H, 2dd, J 9, 4.9 Hz), 6.85, 6.87 (together 1H, 2s), 7.52, 7.54 (together 1H, 2d, J 9 Hz); [mass spectrum: +ve ion (3-nitrobenzyl alcohol-sodium acetate) MH+(582) MNa+(604)].

来源