Reaktion #481744

Reaktionsgleichung

water

n-Butyllithium

5-chloro-3-methylbenzo(b)thiophene

ethyl chloroformate

→

ethyl 5-chloro-3-methylbenzo(b)thiophene-2-carboxylate

Ausbeute 67.0%

Lösungsmittel

hexane

ethyl ether-

ethyl ether

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.STIRRINGThe mixture was stirred for 30 minutes
2. 2
   workup.STIRRINGThe mixture was stirred at 0° C. for 30 minutes and at 25° C. for 1.5 hours
3. 3
   Sonstigethe organic phase was dried
4. 4
   Einengenconcentrated
5. 5
   Sonstigetriturated with hexane

Vorschrift

n-Butyllithium in hexane (2.6 M, 2.3 ml) was added to a solution of 5-chloro-3-methylbenzo(b)thiophene (1,0 g, 6 mmol) in ethyl ether-(20 ml) stirred at 0° C. under argon. The mixture was stirred for 30 minutes and transferred slowly under argon pressure to a stirred solution of ethyl chloroformate (0.63 g, 6 mmol) in ethyl ether (20 ml). The mixture was stirred at 0° C. for 30 minutes and at 25° C. for 1.5 hours. The mixture was treated with water and the organic phase was dried, concentrated and triturated with hexane to give 1.0 g (67%) of ethyl 5-chloro-3-methylbenzo(b)thiophene-2-carboxylate: mp 92.5-94° C.

Quelle