Reaktion #55574

Reaktionsgleichung

diisopropylamine

n-butyllithium

Methyl iodide

3-ethylcyclobutanecarboxlic acid

hydrochloric acid

→

title compound

Ausbeute 109.9%

1-Methyl-3-ethylcyclobutanecarboxylic acid

Ausbeute 109.9%

Lösungsmittel

tetrahydrofuran

hexane

tetrahydrofuran

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.ADDITIONwas added dropwise
2. 2
   Temperaturwhile maintaining the temperature below about 5° C
3. 3
   Temperaturcooling
4. 4
   Temperaturwith cooling for 15 min
5. 5
   Temperaturwithout cooling for 2 hr
6. 6
   workup.STIRRINGThe mixture was then stirred with ice-methanol bath
7. 7
   workup.ADDITIONwas added dropwise until the resultant aqueous phase
8. 8
   SonstigeThe aqueous phase was separated
9. 9
   Extraktionextracted twice with ether
10. 10
    ExtraktionThe combined ether extract
11. 11
    Trocknenwas dried over anhydrous magnesium sulfate
12. 12
    Sonstigethe solvent removed in vacuo

Vorschrift

A solution of 19.9 ml (140 mmol) of dry diisopropylamine in 100 ml of dry tetrahydrofuran was stirred in under an argon atmosphere and 63.6 ml (140 mmol) of a solution of n-butyllithium (2.2 M) in hexane was added dropwise thereto while maintaining the temperature below about 5° C. The resultant mixture was then stirred for 15 min with ice-bath cooling. A solution of 8.2 g (64 mmol) of 3-ethylcyclobutanecarboxlic acid (prepared in Example 1E) in 15 ml of dry tetrahydrofuran was added dropwise to the reaction mixture and stirred with cooling for 15 min. Methyl iodide (4.36 ml, 70 mmol) was added to the reaction mixture dropwise and the resultant mixture was stirred without cooling for 2 hr. The mixture was then stirred with ice-methanol bath cooling as 10% hydrochloric acid was added dropwise until the resultant aqueous phase was acidic (about 25 ml was used). The aqueous phase was separated and extracted twice with ether. The combined ether extract was dried over anhydrous magnesium sulfate and the solvent removed in vacuo to yield 10 g of the title compound having the following physical characteristics:

Quelle