Methanol → 2H-Pyran-4-carboxylic acid, tetrahydro-, methyl ester
Reaction equation
[C:1]([O:4][CH2:5][CH2:6][CH:7]1[CH2:11][CH2:10][O:9][C:8]1=[O:12])(=O)C.CO>O>[O:4]1[CH2:1][CH2:11][CH:7]([C:8]([O:9][CH3:10])=[O:12])[CH2:6][CH2:5]1Participants
4
Reactant 2
Product 1
Reagents, catalysts & solvents 1
Procedure
A solution consisting of 53 wt % of 3-(2'-acetoxyethyl)-dihydro-2(3H)furanone, 39 wt % of methanol, and 8 wt % of water was evaporated at a rate 25 g per hour and the vapors were passed at a temperature of 250° C. over 90 g of aluminum oxide catalyst (diameter 1.5 mm) in a tubular reactor. The gaseous effluent was condensed in cold traps and analyzed by gas chromatography. The experiment was carried out for a period of 12 h and the total amount of starting material used was 600 g. 62 mol % of methyl tetrahydropyran-4-carboxylate was formed, plus 20 mol % of 3-(2'-methoxyethyl)-dihydro-2(3H)furanone and 3 mol % of 5-oxaspiro-[2.4]heptan-4-one. The conversion of 3-(2'-acetoxyethyl)-dihydro-2(3H)furanone was better than 99%.