Reaktion #49871

Reaktionsgleichung

ethyl 1-methyl-5-(phenylmethoxy)-1H-indole-2-carboxylate

isopropylmagnesium chloride

ether

thionyl chloride

→

product

Ausbeute 53.0%

Ethyl 1-methyl-3-[(1-methylethyl)sulfinyl]-5-(phenylmethoxy)-1H-indole-2-carboxylate

Ausbeute 53.0%

Lösungsmittel

hexane

chloroform

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.STIRRINGstirring
2. 2
   workup.WAITis continued for 30 minutes
3. 3
   FiltrationThe crude indole sulfinyl chloride intermediate is filtered
4. 4
   Waschenwashed with hexane
5. 5
   workup.DISSOLUTIONdissolved in 200 mL of tetrahydrofuran
6. 6
   workup.STIRRINGAfter stirring for 15 minutes
7. 7
   Sonstigethe reaction mixture is quenched by the dropwise addition of 20 mL of 2.0N HCl
8. 8
   TemperaturThe reaction mixture is warmed to room temperature
9. 9
   workup.ADDITIONdiluted with water
10. 10
    Extraktionextracted with ethyl acetate
11. 11
    WaschenThe combined organic layers are washed with brine
12. 12
    Trocknendried (anhydrous magnesium sulfate)
13. 13
    Sonstigeevaporated
14. 14
    SonstigeThe residue is triturated with ether
15. 15
    Sonstigeto give a solid which
16. 16
    Sonstigeis recrystallized from aqueous methanol

Vorschrift

A slurry of ethyl 1-methyl-5-(phenylmethoxy)-1H-indole-2-carboxylate (10.0 g, 32 mmol; Monge Vega A, et al., An. Ouim. 1976;72:267) in 30 mL of chloroform is treated dropwise with thionyl chloride (9.5 mL, 15.5 g, 130 mmol). After stirring for 20 minutes, 90 mL of hexane is added, and stirring is continued for 30 minutes. The crude indole sulfinyl chloride intermediate is filtered, washed with hexane, and dissolved in 200 mL of tetrahydrofuran. The solution is cooled to -78° C. and treated dropwise with a 2.0M solution of isopropylmagnesium chloride in ether (16.4 mL, 32.8 mmol). After stirring for 15 minutes, the reaction mixture is quenched by the dropwise addition of 20 mL of 2.0N HCl. The reaction mixture is warmed to room temperature, diluted with water, and extracted with ethyl acetate. The combined organic layers are washed with brine, dried (anhydrous magnesium sulfate), and evaporated. The residue is triturated with ether to give a solid which is recrystallized from aqueous methanol to yield 6.8 g (53%) of product; mp 142°-145° C.

Quelle