Reaktion #214425

Reaktionsgleichung

sodium borohydride

4-chloro-1-(4-chlorophenoxy)-3,3-dimethyl-1-(imidazol-1-yl)-butan-2-one naphthalene-1,5-disulphonate

Compound 15

4-chloro-1-(4-chlorophenoxy)-3,3-dimethyl-1-(imidazol-1-yl)-butan-2-one naphthalene-1,5-disulphonate

sodium bicarbonate

→

4-chloro-1-(4-chlorophenoxy)-3,3-dimethyl-1-(imidazol-1-yl)-butan-2-ol

Ausbeute 75.0%

Lösungsmittel

isopropanol

methylene chloride

Reaktionsbedingungen

Aufarbeitung

1. 1
   SonstigeThe organic phase was separated off
2. 2
   Trocknendried over sodium sulphate
3. 3
   Einengenconcentrated
4. 4
   workup.DISTILLATIONby distilling off the solvent in vacuo
5. 5
   SonstigeThe base thus obtained
6. 6
   workup.DISTILLATIONthe isopropanol was then distilled off
7. 7
   workup.ADDITIONafter adding 100 ml of water
8. 8
   workup.STIRRINGwas stirred for a further 15 hours at room temperature
9. 9
   SonstigeThe organic phase was then separated off
10. 10
    Waschenwashed twice with 50 ml of water at a time
11. 11
    Trocknendried over sodium sulphate
12. 12
    Einengenconcentrated
13. 13
    Sonstigeto crystallize

Vorschrift

18.8 g (0.04 mol) of 4-chloro-1-(4-chlorophenoxy)-3,3-dimethyl-1-(imidazol-1-yl)-butan-2-one naphthalene-1,5-disulphonate [=Compound 15; prepared in accordance with Example 1, in 81% yield] were suspended in 100 ml of methylene chloride and 100 ml of sodium bicarbonate solution were added. The organic phase was separated off, dried over sodium sulphate and concentrated by distilling off the solvent in vacuo. The base thus obtained was taken up in 100 ml of isopropanol and 2 g (0.05 mol) of sodium borohydride were introduced incrementally at 5° to 10° C. The mixture was stirred for 15 hours at room temperature and the isopropanol was then distilled off. The residue was taken up in 100 ml of methylene chloride and, after adding 100 ml of water, was stirred for a further 15 hours at room temperature. The organic phase was then separated off, washed twice with 50 ml of water at a time, dried over sodium sulphate and concentrated. The oil which remained was boiled up in 100 ml of petroleum ether, which caused it to crystallize. 9.8 g (75% of theory) of 4-chloro-1-(4-chlorophenoxy)-3,3-dimethyl-1-(imidazol-1-yl)-butan-2-ol were obtained as an isomer mixture (erythro form and threo form) of melting point 120°-125° C.

Quelle