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ChemicalBook CAS DataBase List ethyl 1,4-dioxaspiro[4.5]decane-8-carboxylate
1489-97-0

ethyl 1,4-dioxaspiro[4.5]decane-8-carboxylate synthesis

8synthesis methods
-

Yield:1489-97-0 100%

Reaction Conditions:

with toluene-4-sulfonic acid in toluene at 20 - 25; for 20 h;Product distribution / selectivity;

Steps:

a; A
4-Oxo-cyclohexanecarboxylic acid ethyl ester (52.8 g, 0.31 mol, Merck, order no. 814249, ethylene glycol (67.4 g, 1.08 mol) and p-toluenesulfonic acid (0.7 g) in toluene (160 ml) were stirred at RT for 20 h, the reaction solution was poured into diethyl ether (300 ml) and the mixture was washed with water, sodium bicarbonate solution and sodium chloride solution. The solution was dried (Na2SO4) and concentrated i. vac. and the colourless liquid which remained was processed further without purification.Yield: 66.5 g (100%)1H-NMR (CDCl3): 1.24 (t, 3H); 1.53 (m, 2H); 1.76 (m, 4H); 1.92 (m, 2H); 2.31 (m, 1H); 3.91 (s, 4H); 4.11 (q, 2H).13C-NMR (CDCl3): 14.28 (q); 26.32 (t); 33.76 (t); 41.59 (d); 60.14 (t); 64.21 (t); 107.90 (d); 174.77 (s).Stage AEthylene glycol (1.08 mol) and p-toluenesulfonic acid (0.7 g) were added to a solution of 4-oxo-cyclohexanecarboxylic acid ethyl ester (0.31 mol) in toluene (160 ml) and the mixture was stirred at 25° C. for 20 h. Ethyl acetate (300 ml) was then added. The organic phase separated off was washed with water, aqueous saturated NaHCO3 solution and NaCl solution. After drying of the organic phase over Na2SO4 and filtration, the solvent was removed in vacuo. The product was employed in the next stage without further purification.

References:

Gruenenthal GmbH US2008/306084, 2008, A1 Location in patent:Page/Page column 33-34; 44-45

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