반응 #1929089

반응 방정식

NH4Cl

p-nitrobenzyl bromide

bisphosphonate

Tetraallyl Methylenebisphosphonate

NaH

→

nitrobenzyl bisphosphonate

수율 39.2%

Tetraallyl 1-(4-nitrobenzyl)methylenebisphosphonate

수율 39.2%

용매

water

THF

DMF

반응 조건

후처리

1. 1
   workup.STIRRINGthe mixture was stirred for 3 h at room temperature
2. 2
   추출extracted with CH2Cl2 (3×)
3. 3
   세척The combined organic layers were washed with saturated brine once
4. 4
   건조dried over MgSO4
5. 5
   농축concentrated in vacuo
6. 6
   기타The crude product was purified by flash chromatography on silica gel using a gradient of 0-50% EtOAc in CH2Cl2 as eluant

실험 절차

To a solution of bisphosphonate 23 (8.02 g, 23.9 mmol) in DMF (24 mL) was added NaH (60% dispersion in mineral oil, 954 mg, 23.9 mmol) portionwise and the solution was stirred for 1.5 h at room temperature. A solution of p-nitrobenzyl bromide (7.75 g, 35.9 mmol) in THF (32 mL) was added and the mixture was stirred for 3 h at room temperature. It was then poured into a mixture of saturated aqueous NH4Cl solution and water and extracted with CH2Cl2 (3×). The combined organic layers were washed with saturated brine once, dried over MgSO4 and concentrated in vacuo. The crude product was purified by flash chromatography on silica gel using a gradient of 0-50% EtOAc in CH2Cl2 as eluant to provide nitrobenzyl bisphosphonate 26 as a clear yellow oil (4.42 g, 9.38 mmol, 39%). 1H NMR (400 MHz, CDCl3) δ 2.73 (tt, J=23.8, 6.5 Hz, 1H), 3.37 (dt, J=16.4, 6.5 Hz, 2H), 4.51-4.61 (m, 8H), 5.21-5.25 (m, 4H), 5.29-5.35 (m, 4H), 5.83-5.93 (m, 4H), 7.44 (d, J=8.8 Hz, 2H), 8.14 (d, J=8.8 Hz, 2H).

출처