反应 #80264

反应方程式

8-(N-Cbz-amino)-1,3-octanediol

Diisopropylethylamine

4,4-dimethoxytrityl chloride

tetrahydrofuran

→

8-(N-Cbz-amino)-3-hydroxy-1-(4,4'-dimethoxytrityloxy)octane

溶剂

pyridine

反应条件

后处理

1. 1
   其他evaporated in vacuo
2. 2
   workup.DISSOLUTIONredissolved in anhydrous pyridine (200 mL)
3. 3
   温度cooled in an ice bath
4. 4
   workup.STIRRINGStirring
5. 5
   workup.ADDITIONafter the addition
6. 6
   其他The mixture was evaporated in vacuo
7. 7
   其他purified by column chromatography on silica gel
8. 8
   洗涤eluting with 20:80:1 ethyl acetate
9. 9
   其他Evaporation of the appropriate fractions

实验过程

8-(N-Cbz-amino)-1,3-octanediol (4, 25 g, 85 mmoles ) was dissolved in anhydrous pyridine (200 mL), evaporated in vacuo and redissolved in anhydrous pyridine (200 mL). Diisopropylethylamine (38.1 mL, 88 mmoles) and 4-dimethylaminopyridine (170 mg) were added. The mixture was stirred under nitrogen and cooled in an ice bath while adding 4,4-dimethoxytrityl chloride (30 g, 88 mmoles) in tetrahydrofuran (200 mL) dropwise over 1.5 hours. Stirring was continued for 15 minutes after the addition was complete. The mixture was evaporated in vacuo and purified by column chromatography on silica gel, eluting with 20:80:1 ethyl acetate:cyclohexane:triethylamine, then 50:50:1 ethyl acetate:cyclohexane:triethylamine and finally, 100:1 ethyl acetate:triethylamine. Evaporation of the appropriate fractions gave 8-(N-Cbz-amino)-3-hydroxy-1-(4,4'-dimethoxytrityloxy)octane (44 g) as a crisp foam. Mass Spectrum: (M+K)+ @m/z 636. 8-(N-Cbz-amino)-3-hydroxy-1-(4,4'-dimethoxytrityloxy)octane (28.4 g, 47.6 mmoles) was dissolved in methanol (200 mL) and hydrogenated over 10% palladium on carbon (2.84 g) @45 psi hydrogen for 2.5 hours. After filtration and evaporation in vacuo there remained 8-(N-Cbz-amino)-1,3-octanediol (21.5 g). Mass Spectrum: (M+K)+ @m/z 502.

来源