Diethyl Malonate → 1,3-Diethyl 2-(1-methylbutyl)propanedioate

HRID 1768929

Reaktionsgleichung

Reaktionsgleichung von HRID 1768929
[Na].[C:2]([O:10][CH2:11][CH3:12])(=[O:9])[CH2:3][C:4]([O:6][CH2:7][CH3:8])=[O:5].[O-]CC.[Na+:16].Br[CH:18]([CH2:20][CH2:21][CH3:22])[CH3:19]>C(O)C>[O-:5][CH2:4][CH3:3].[Na+:16].[CH3:19][CH:18]([CH:3]([C:4]([O:6][CH2:7][CH3:8])=[O:5])[C:2]([O:10][CH2:11][CH3:12])=[O:9])[CH2:20][CH2:21][CH3:22]

Komponenten

7

Edukt 4

HCID 7761Diethyl MalonateHCID 78902-BromopentaneHCID 2723922Sodium ethoxideHCID 5360545Sodium

Produkt 2

HCID 954491,3-Diethyl 2-(1-methylbutyl)propanedioateHCID 2723922Sodium ethoxide

Reagenzien, Katalysatoren, Lösungsmittel 1

HCID 702EthanolLösungsmittel2×

Reaktionsbedingungen

Temperatur
80 °C

Versuchsvorschrift

Sodium ethoxide was prepared from sodium metal (7.61 g) and absolute ethanol (200 ml). Diethyl malonate (50.3 ml) was added dropwise to the ethanol containing sodium ethoxide. After heating to 80° C., 2-bromopentane (50 g) was added and the mixture was reflued for 24 h. Diethyl (2-pentyl)malonate (62.7 g) was obtained after the usual work-up. Diethyl (2-pentyl)malonate was added to a 50% potassium hydroxide solution and the mixture was heated for 3 h while water/ethanol being distilled off. After cooling, the solution was acidified with concentrated hydrochloric acid. Then, the solution was extracted with ethyl acetate. The extract was concentrated under reduced pressure, and the resulting product was heated to 180° C. until bubbling ceased. After distillation, colorless 3R,S-methy-caproic acid was obtained. Yield: 27.7 g (35%), b.p. 200° C./760 mmHg.

Quellen und Nachweise

ORD-Eintrag
ord-15184c570331498ba2f50f71724832bc
Quelldatensatz
uspto-grants-1995_01
Patentnummer
US05380709

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