Gamma-Butyrolactone → Diethyl Maleate
Reaction equation
C1(=O)OCCC1.[C:7]([O:16][CH2:17][CH3:18])(=[O:15])[CH2:8][CH2:9][C:10]([O:12][CH2:13][CH3:14])=[O:11]>>[C:10]([O:12][CH2:13][CH3:14])(=[O:11])/[CH:9]=[CH:8]\[C:7]([O:16][CH2:17][CH3:18])=[O:15]Participants
Procedure
In EP-A-0255400 there is described a process for the production of substantially pure gamma-butyrolactone from a feed mixture containing a major molar amount of gamma-butyrolactone and a minor amount of diethyl succinate. Such a feed mixture may result from hydrogenation of diethyl maleate according to the teachings of EP-A-0143634, WO-A-86/03189, and/or WO-A-86/07358. In EP-A-0255400 which was published on Feb. 3, 1988, there is described a process in which the "light ends", i.e. a mixture of tetrahydrofuran, ethanol, water, and n-butanol, are stripped off in a first distillation column which is operated under vacuum at a pressure of 0.27 bar with a head temperature of 48° C. The "light ends" which are recovered overhead are passed to a second distillation column which is operated at 1.2 bar at a head temperature of 58° C. A first tetrahydrofuran/water azeotrope is recovered overhead from this second distillation column which is passed to a third distillation column operated at 7.0 bar with a head temperature of 126° C. Essentially pure tetrahydrofuran is recovered as a bottom product from the third distillation column, whilst the overhead product therefrom is a second tetrahydrofuran/water azeotrope which is markedly richer in water than the first tetrahydrofuran/water azeotrope from the second column. This second azeotrope is recycled to the second column.
Sources & evidence
- ORD record
- ord-74ce90af140d4e8e8142eca7a0cda8a7
- Source dataset
- uspto-grants-1990_04
- Patent number
- US04919765
Reaction notes
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