Reaktion #161321

Reaktionsgleichung

Levulinic acid

diethylene glycol

levulinic acid

→

2-(2-hydroxyethoxy)ethyl 4-(2-(2-hydroxyethoxy)ethoxy)pentanoate

Ausbeute 23.4%

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigepurged with nitrogen three times
2. 2
   Sonstigereacted with 1000 psi of hydrogen for 65 hrs
3. 3
   workup.DISTILLATIONDiethylene glycol is distilled off at 70-72° C./0.06 mm
4. 4
   Sonstigeto give 15.6 g of the crude product, which
5. 5
   Sonstigeis chromatographed on silica gel using at first neat methylene chloride

Vorschrift

Levulinic acid (11.6 g; 0.1 mol), diethylene glycol (63.6 g; 0.6 mol), and 2.32 g of 10% Pd/C from Aldrich (20 wt % relative to levulinic acid) are charged to a Parr reactor, purged with nitrogen three times, heated to 230° C. with stirring, and reacted with 1000 psi of hydrogen for 65 hrs. GC analysis reveals that the reaction is complete. Diethylene glycol is distilled off at 70-72° C./0.06 mm to give 15.6 g of the crude product, which is chromatographed on silica gel using at first neat methylene chloride and then methylene chloride-methanol from 30:1 to isolate 6.9 g of 2-(2-hydroxyethoxy)ethyl 4-(2-(2-hydroxyethoxy)ethoxy)pentanoate. 1H NMR (δ, ppm, CDCl3): 1.16 d (3H, CH3), 1.81 m (2H, CH2), 2.46 m (2H, CH2CO), 3.1 (broad, 2H, OH), 3.50 m (3H, CH2O, CH), 3.61 m (14H, 7CH2O), 4.25 m (2H, COOCH2). 13C NMR (δ, ppm, CDCl3): 19.30 (CH3); 30.01; 31.27 (CH2 groups); 61.38; 61.54; 63.22; 67.64; 68.88; 70.48; 72.33; 72.37 (CH2O groups), 74.68 (CH), 173.57 (COO). Mass spectrum: m/e 294 (M+).

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