반응 #530918

반응 방정식

HCl

N-(β-hydroxy-3-methoxy-α,α-dimethylphenethyl)-3,4-dimethoxybenzeneacetamide

tetrahydrofuran

THF

→

α-(1-{[2-(3,4-dimethoxyphenyl)ethyl]amino}-1-methylethyl)-3-methoxybenzenemethanol hydrochloride

수율 39.0%

용매

Water

water

반응 조건

후처리

1. 1
   workup.ADDITIONAfter addition
2. 2
   온도Then the acidic reaction mixture is heated at 65° C. for 1 hour
3. 3
   기타to remove most of the tetrahydrofuran
4. 4
   기타destroy excess BH3
5. 5
   온도Next, the mixture is cooled with ice and basicified with NH4OH
6. 6
   추출The mixture is extracted twice with 1 l
7. 7
   건조The combined organic extracts are dried (Na2SO4)
8. 8
   기타evaporated to dryness in vacuo
9. 9
   workup.DISSOLUTIONby dissolving the residue in 250 ml
10. 10
    workup.ADDITIONethyl acetate and adding a solution of ethyl acetate saturated with dry HCl to pH 2.0
11. 11
    기타of crude solid is obtained
12. 12
    기타which is recrystallized from 300 ml
13. 13
    기타hot isopropanol to give 18.5 g

실험 절차

To a solution of 45 g. (0.12 mole) of N-(β-hydroxy-3-methoxy-α,α-dimethylphenethyl)-3,4-dimethoxybenzeneacetamide in 500 ml. dry tetrahydrofuran is added 200 ml. 1 M (0.2 mole) of BH3 /THF solution over 30 minutes at 0° C. with stirring. After addition, the reaction is allowed to stir overnight at room temperature. Water is added dropwise with caution until effervescence ceases, then 50 ml. more water is added all at once. Aqueous HCl (10%) is added to pH 1.0. Then the acidic reaction mixture is heated at 65° C. for 1 hour to remove most of the tetrahydrofuran and destroy excess BH3. Next, the mixture is cooled with ice and basicified with NH4OH. The mixture is extracted twice with 1 l. ethyl acetate. The combined organic extracts are dried (Na2SO4) and evaporated to dryness in vacuo. The crude hydrochloride is made by dissolving the residue in 250 ml. ethyl acetate and adding a solution of ethyl acetate saturated with dry HCl to pH 2.0. On standing, 25 g. of crude solid is obtained, which is recrystallized from 300 ml. hot isopropanol to give 18.5 g. (39% yield) of α-(1-{[2-(3,4-dimethoxyphenyl)ethyl]amino}-1-methylethyl)-3-methoxybenzenemethanol hydrochloride as a white crystalline solid of analytical purity; m.p. 185°-186° C.

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