Réaction #4381

Équation de réaction

1-(2-iodo-5-methoxyphenyl)heptan-2-one

dimethylamine

dimethylamine hydrochloride

sodium cyanoborohydride

hydrogen chloride

→

2-Iodo-5-methoxy-N,N-dimethylalphapentylbenzenepropanamine hydrochloride

Solvants

methanol

methanol

methanol

Conditions de réaction

Traitement

1. 1
   workup.STIRRINGStirring
2. 2
   workup.WAITwas continued an additional two hours
3. 3
   workup.ADDITIONthe reaction mixture acidified to pH 1 by addition of concentrated hyirochloric acid
4. 4
   AutreThe solvent was evaporated in vacuo
5. 5
   Autrethe residue partitioned between methylene chloride and water
6. 6
   Autrethe methylene chloride layer separated
7. 7
   Lavagewashed with Na2S2O5 solution
8. 8
   SéchageThe organic phase was dried over anhydrous potassium carbonate
9. 9
   Autreevaporated in vacuo
10. 10
    Autreto yield a yellow oil
11. 11
    AutreThe solvent was removed in vacuo
12. 12
    workup.DISSOLUTIONthe residue dissolved in 45 ml of refluxing ethyl acetate
13. 13
    AutreSome slight turbidity was removed by filtration
14. 14
    Filtrationthrough filter aid
15. 15
    workup.ADDITIONdiluted with 20 ml of diethyl ether
16. 16
    TempératureThe solution was cooled overnight in a refrigerator
17. 17
    Autrethe resulting solid, 3.34 g, removed by filtration
18. 18
    AutreThe filtrate was evaporated in vacuo
19. 19
    Autrethe residue triturated with ether
20. 20
    Autreto yield a second crop of off-white solid, 1.66 g
21. 21
    AutreOne recrystallization from ethyl acetate yielded pure 2-iodo-5-methoxy-N,N-dimethylalphapentylbenzenepropanamine hydrochloride, mp 100°-103° C.

Mode opératoire

A mixture of 13.0 g (0.036 mole) of 1-(2-iodo-5-methoxyphenyl)heptan-2-one, 46.6 ml (0.18 mole) of a solution of 3.86 M dimethylamine in methanol, 8.24 g (0.101 mole) of dimethylamine hydrochloride, 100 ml of methanol and 1.82 g (0.029 mole) of sodium cyanoborohydride was stirred overnight under an atmosphere of nitrogen. Stirring was continued an additional two hours and the reaction mixture acidified to pH 1 by addition of concentrated hyirochloric acid. The solvent was evaporated in vacuo, the residue partitioned between methylene chloride and water, and the methylene chloride layer separated, washed with Na2S2O5 solution followed by a washing with 3 M sodium hydroxide solution. The organic phase was dried over anhydrous potassium carbonate and evaporated in vacuo to yield a yellow oil. The oil was dissolved in methanol and the solution treated with ethereal hydrogen chloride to pH 5. The solvent was removed in vacuo and the residue dissolved in 45 ml of refluxing ethyl acetate. Some slight turbidity was removed by filtration through filter aid. The filtrate was cooled to room temperature and diluted with 20 ml of diethyl ether. The solution was cooled overnight in a refrigerator and the resulting solid, 3.34 g, removed by filtration. The filtrate was evaporated in vacuo, the residue triturated with ether and seeded to yield a second crop of off-white solid, 1.66 g. One recrystallization from ethyl acetate yielded pure 2-iodo-5-methoxy-N,N-dimethylalphapentylbenzenepropanamine hydrochloride, mp 100°-103° C.

Source