Reaktion #412950

Reaktionsgleichung

hydrochloric acid

methyl 2-cyano-3-phenylbutyrate

methyl 2,4-dibromobutyrate

potassium carbonate

→

Dimethyl 2-phenyl-3-cyano-6-bromohexane-3,4-dicarboxylate

Lösungsmittel

DMSO

Reaktionsbedingungen

Aufarbeitung

1. 1
   ExtraktionThe aqueous solution was extracted several times with ether
2. 2
   WaschenThe combined organic solution was washed sequentially with cold aqueous sodium bicarbonate and brine
3. 3
   Trocknendried over magnesium sulfate
4. 4
   SonstigeAfter removal of the solvent
5. 5
   workup.DISTILLATIONthe residue was purified by Kugelrohr distillation (100° C., 30 microns)
6. 6
   Sonstigeto remove low boiling materials
7. 7
   Sonstigethe title bromide condensation product (μ<95% GC purity)

Vorschrift

A mixture of methyl 2-cyano-3-phenylbutyrate (78 g, 0.37 mole), methyl 2,4-dibromobutyrate (122 g, 0.47 mole), potassium carbonate (65 g, 0.47 mole) and DMSO (50 ml) was stirred on a ball mill apparatus. The reaction was completed in four hours. Ice water was added and the mixture was neutralized by adding cold hydrochloric acid. The aqueous solution was extracted several times with ether. The combined organic solution was washed sequentially with cold aqueous sodium bicarbonate and brine, then dried over magnesium sulfate. After removal of the solvent, the residue was purified by Kugelrohr distillation (100° C., 30 microns) to remove low boiling materials. The remaining oily residue (118 g., 84%) was found to be mainly the title bromide condensation product (μ<95% GC purity). MS m/e (% relative intensity) 383(M.+, 3) 381 (3), 202 (33), 182 (7), 180 (7), 105 (100).

Quelle