反応 #6520

反応方程式

17

(2R,5S)-1-[2-(Butyldiphenylsiloxymethyl)-1,3-oxathiolan-5-yl]cytosine

tetrabutylammonium fluoride

→

3

収率 75.0%

(2R,5S)-1-[2-(Hydroxymethyl)-1,3-oxathiolan-5-yl]cytosine

収率 75.0%

溶媒

THF

THF

反応条件

後処理

1. 1
   その他the disappearance of starting material (30 min)
2. 2
   濃縮The reaction mixture was concentrated under reduced pressure
3. 3
   その他the residue purified by preparative TLC

実験手順

To a solution of the β anomer 17 (0.15 g, 0.32 mmol) in THF (25 mL) was added tetrabutylammonium fluoride 1M in THF (0.35 mL, 0.35 mmol, 1.1 eq) and the reaction was allowed to stir at room temperature until TLC indicated the disappearance of starting material (30 min). The reaction mixture was concentrated under reduced pressure and the residue purified by preparative TLC using 12% MeOH/CHCl3 as development solvent to give 0.055 g (75%) of 3 from ethyl ether/MeOH (trace) as a white crystalline solid. [α]23D =-121.6 (c 1.1, MeOH) (for the S,R isomer 2 [α]23D =120.96 (c 1.06, MeOH)); 1H NMR: ((CD3)2SO) δ 3.03 (dd, J5,4a =4.4 Hz, J4a,4b =11.86 Hz, 1 H, 4a-H), 3.43 (dd, J5,4b =5.3 Hz, J4a,4b =11.86 Hz, 1 H, 4b-H), 3.80 (app t on D2O exchange goes to d, J2,2-CH2-OR =4.17 Hz, 2 H, 2-CH2 -OH), 5.27 (t, J2-CH2,OH =4.6 Hz, 1 H, 2-CH2OH), 5.22 (t, J2,2-CH2-OH =4.17 Hz, 1 H, 2-H), 5.88 (d, J5,6 =7.47 Hz, 1 H, H-5), 6.21 (app t, J=5.05 and 4.84 Hz, 1 H, 5-H), 7.19 (bs, 2 H, NH2), 7.89 (d, J5,6 =7.47 Hz, 1 H, H-6).

出典