반응 #3746

반응 방정식

methanol

Triethylamine

thymidine

4,4'-dimethoxytrityl chloride

→

5

수율 85.3%

5'-O-(4,4'-dimethoxytrityl) thymidine

수율 85.3%

용매

THF

반응 조건

후처리

1. 1
   workup.STIRRINGThe solution was stirred at room temperature for 2 hours
2. 2
   workup.ADDITIONwas added
3. 3
   기타to consume the excess DMTrCl
4. 4
   workup.STIRRINGThe mixture was stirred for 5 minutes
5. 5
   기타the solvent removed by rotary evaporation
6. 6
   workup.DISSOLUTIONThe residue was dissolved in 250 ml of ethyl acetate
7. 7
   세척the solution was washed with saturated NaHCO3
8. 8
   건조dried over MgSO4
9. 9
   기타The solid was recrystallized from ethyl acetate/hexane

실험 절차

Triethylamine (10 ml) in 200 ml THF was injected into a solid mixture of 6.8 g (28.0 mmol) thymidine and 10.2 g (28.6 mmol) 4,4'-dimethoxytrityl chloride under nitrogen with stirring. The solution was stirred at room temperature for 2 hours. After completion of the reaction, 10 ml methanol was added to consume the excess DMTrCl. The mixture was stirred for 5 minutes and the solvent removed by rotary evaporation. The residue was dissolved in 250 ml of ethyl acetate and the solution was washed with saturated NaHCO3 and dried over MgSO4. The solid was recrystallized from ethyl acetate/hexane to obtain 13.0 g 5'-protected thymidine 16 (85.6%).: m.p. 124°-126° C.; 1H NMR (200 MHz, CDCl3) δ8.97 (s, 1H, NH), 7.60 (m, 1H, H-6), 6.72-7.42 (m, 13H, Ph), 6.42 (m, 1H, H-1'), 4.56 (m, 1H, H-3'), 4.05 (m, 1H, H-4'), 3.78 (s, 6H, OMe2), 3.41 (m, 2H, H-5'), 2.62 (m, 1H, OH), 2.46 (m, 2H, H-2'), 1.46 (s, 3H, Me); 13C NMR (50 MHz, CDCl3) δ163.0 (C-4), 157.6, 149.8 (C-2), 143.5, 135.0 (C-6), 134.7, 134.6, 129.4, 127.4, 127.3, 126.5, 112.8, 110.9 (C-5), 86.7 (C-4'), 86.2, 84.7 (C-1'), 72.5 (C-3'), 63.8 (C-5'), 55.5 (OCH3), 41.3 (C-2'), 12.5 (CH3).

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