Reaktion #572155

Reaktionsgleichung

1-bromo-2-methylpropane

Butyl lithium

1-methyl-4-(phenylmethyl)piperazinone

1-Methyl-4-(phenylmethyl)piperazinone

diisopropylamine

→

title compound

1-Methyl-3-(2-methylpropyl)-4-(phenylmethyl)piperazinone

Lösungsmittel

ethyl acetate

THF

hexamethylphosphorotriamide

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturto warm to 20°-25°
2. 2
   Temperaturthe solution is refluxed for 3 hours
3. 3
   SonstigeThe THF is removed under reduced pressure
4. 4
   Sonstigethe residual oil is partitioned between chloroform and water
5. 5
   SonstigeEvaporation of the chloroform
6. 6
   Sonstigegives an oil which
7. 7
   Sonstigechromatographed on silica gel
8. 8
   WaschenElution of the column with ethyl acetate and pooling of the appropriate fractions

Vorschrift

Butyl lithium (8.0 ml. of 1.6M in hexane, 0.012 mole) is added at -60° to a stirred solution of 1-methyl-4-(phenylmethyl)piperazinone (Example 46, 2.04 g., 0.010 mole), diisopropylamine (1.1 g., 0.011 mole) and hexamethylphosphorotriamide (2.0 ml.) in THF (25 ml.). The solution is allowed to warm to 20°-25°, 1-bromo-2-methylpropane (4.1 g., 0.030 mole) is added and the solution is refluxed for 3 hours. The THF is removed under reduced pressure and the residual oil is partitioned between chloroform and water. Evaporation of the chloroform gives an oil which is dissolved in ethyl acetate and chromatographed on silica gel. Elution of the column with ethyl acetate and pooling of the appropriate fractions gives the title compound.

Quelle