Method of making a dialdeyhde

Abstract

We have discovered that a di-epoxide can be converted to a dialdehyde using an amorphous silica-alumina catalyst. The method comprises contacting a di-epoxide mixed in an organic solvent with a silica-alumina catalyst to form a solvent and dialdehyde reaction product mixture and separating said dialdehyde from said reaction mixture. The dialdehydes have utility as chemical intermediates, and particular utility in processes to make enol ether compounds which can be used in applications as plasticizers, diluents, wetting agents, coalescing aids and as intermediates in chemical processes.

Claims

1. A method of making a dialdehyde comprising contacting a di-epoxide with a silica-alumina catalyst.

2. A method of making a dialdehyde comprising: a. contacting a di-epoxide and an organic solvent with a silica-alumina catalyst to form a solvent and dialdehyde reaction mixture; and b. separating said dialdehyde from said reaction mixture.

3. The method of claim 2 wherein said diepoxide is selected from the group comprising 1,3-bis(2-methyloxiran-2-yl)benzene, 1,4-bis(2-methyloxiran-2-yl)benzene, 1,3-di(oxiran-2-yl)benzene, 1,4-di(oxiran-2-yl)benzene 4,4-bis(2-methyloxiran-2-yl)-1,1-biphenyl, and 2,6-bis(2-methyloxiran-2-yl)naphthalene and mixtures thereof.

4. The method of claim 2 wherein said di-epoxides is 1,3-bis(2-methyloxiran-2-yl)benzene, 1,4-bis(2-methyloxiran-2-yl)benzene.

5. The method of claim 2 wherein said silica alumina catalyst is selected from the group consisting of silica-alumina Grade 135, amorphous silica-aluminas, and acid-washed bleaching earths.

6. The method of claim 2 wherein said solvent is selected from the group consisting of heptane, toluene, chlorobenzene, para-xylene, meta-xylene, ortho-xylene, ethyl acetate, acetonitrile, acetone, methyl ethyl ketone, methyl isobutyl ketone, and heptane and mixtures thereof.

Description

DETAILED DESCRIPTION

Definitions

(1) In this specification and in the claims that follow, reference will be made to a number of terms, which shall be defined to have the following meanings.

(2) Alcohol means a chemical containing one or more hydroxyl groups.

(3) Aldehyde means a chemical containing one or more C(O)H groups.

(4) As used herein, the terms a, an, and the mean one or more.

(5) As used herein, the term and/or, when used in a list of two or more items, means that any one of the listed items can be employed by itself or any combination of two or more of the listed items can be employed. For example, if a composition is described as containing components A, B, and/or C, the composition can contain A alone; B alone; C alone; A and B in combination; A and C in combination, B and C in combination; or A, B, and C in combination.

(6) As used herein, the terms comprising, comprises, and comprise are open-ended transition terms used to transition from a subject recited before the term to one or more elements recited after the term, where the element or elements listed after the transition term are not necessarily the only elements that make up the subject.

(7) As used herein, the terms including, includes, and include have the same open-ended meaning as comprising, comprises, and comprise provided above.

(8) Chosen from as used herein can be used with or or and. For example, Y is chosen from A, B, and C means Y can be individually A, B, or C. Alternatively, Y is chosen from A, B, or C means Y can be individually A, B, or C; or a combination of A and B, A and C, B and C, or A, B, and C.

(9) Presented herein is a processes to directly convert a diepoxide to a dialdehyde via novel synthesis methods

(10) Mono-epoxide to mono-aldehyde rearrangements are well known. However, when attempting to extend scope to di-aldehyde to di-epoxide rearrangement, the chemistry options are far lacking. For example, common Lewis acids and Bronsted acids lead to oligomerization and the production of complex mixtures of products when a difunctional rearrangement was attempted. Conditions screened include tritylium tetrafluorborate, boron trifluoride, zinc chloride, methanesulfonic acid, solid supported acids (e.g. Amberlyst 15, Nafion NR50)all of which led to complicated reaction mixtures. Other catalysts that have been screened include kaolinte, bentonite, Zeolite Y, acidic aluminum oxide, and silica gel. These conditions all resulted in no reaction. Kaolinite, bentonite, and Zeolite Y are characterized as alumina silicates yet do not possess catalytic activity towards the di-epoxide to dialdehyde transformation of this invention.

(11) We have discovered that a di-epoxide can be directly and cleanly converted to the dialdehyde using an amorphous silica-alumina catalyst.

(12) In one embodiment the method comprises: a. contacting a di-epoxide mixed in an organic solvent with a silica-alumina catalyst to form a solvent and dialdehyde reaction product mixture; and b. separating said dialdehyde from said reaction mixture.

(13) Di-epoxides suitable for the method include 1,3-bis(2-methyloxiran-2-yl)benzene, 1,4-bis(2-methyloxiran-2-yl)benzene, 1,3-di(oxiran-2-yl)benzene, 1,4-di(oxiran-2-yl)benzene 4,4-bis(2-methyloxiran-2-yl)-1,1-biphenyl, and 2,6-bis(2-methyloxiran-2-yl)naphthalene and mixtures thereof.

(14) Preferred di-epoxides for the method include 1,3-bis(2-methyloxiran-2-yl)benzene, 1,4-bis(2-methyloxiran-2-yl)benzene.

(15) Catalysts suitable for the method include silica-alumina Grade 135, amorphous silica-aluminas, and acid-washed bleaching earths.

(16) Solvents suitable for the method include heptane, toluene, chlorobenzene, para-xylene, meta-xylene, ortho-xylene, ethyl acetate, acetonitrile, acetone, methyl ethyl ketone, methyl isobutyl ketone, and heptane and mixtures thereof.

(17) Preferred solvents for the method are toluene, chlorobenzene, and xylenes.

EXAMPLES

Abbreviations

(18) mL is milliliter; hrs or h is hour(s); mm is millimeter; m is meter; GC is gas chromatography; C. is degree Celsius; min is minute; t.sub.R is retention time; g is gram; L is liter; L is microliter; PSD is particle size distribution.

Example 1: Preparation of 2,2(1,4-phenylene)dipropanal [3]

(19) ##STR00001##

(20) A solution of toluene (300 mL) and silica-alumina grade 135 (distributed by Sigma-Aldrich as an amorphous catalyst support, ca. 6.5% Al, PSD100 mesh (99.3%)) (50 g) was heated to reflux in a 1 L 4-neck round-bottom flask fitted with an overhead stirrer, thermocouple, and a Dean-Stark trap. After 4 hrs, ca. 5 mL of water was collected. The mixture was then cooled to 75 C., whereupon 1,4-bis(2-methyloxiran-2-yl)benzene [1] (100 g) was added in 10 g portions over the course of 1 hr. After the last addition, GC indicated complete conversion of 1 to 2,2-(1,4-phenylene)dipropanal [3]. Heating was stopped, and the mixture was allowed to cool to ambient temperature. The silica-alumina was removed via filtration through a 1-micron glass-fiber disc. The filtrate was concentrated under reduced pressure using a rotary evaporator. The crude material was then Kugelrohrdistilled at 1 mm Hg/150 C. to afford pure 2,2-(1,4-phenylene)dipropanal [3]. GC-MS t.sub.R: 14.47 min (Exact mass: 190.10 m/z, found: 190.1 m/z).

Example 2: Preparation of 2,2(1,3-phenylene)dipropanal [6]

(21) ##STR00002##

(22) A solution of toluene (300 mL) and silica-alumina grade 135 (distributed by Sigma-Aldrich as an amorphous catalyst support, ca. 6.5% Al, PSD100 mesh (99.3%)) (50 g) was heated to reflux in a 1 L 4-neck round-bottom flask fitted with an overhead stirrer, thermocouple, and a Dean-Stark trap. After 4 hrs, ca. 5 mL of water was collected. The mixture was then cooled to 75 C., whereupon 1,3-bis(2-methyloxiran-2-yl)benzene [4] (100 g) was added dropwise over the course of 1 hr. After the last addition, GC indicated complete conversion of 4 to 2,2-(1,3-phenylene)dipropanal [3]. Heating was stopped, and the mixture was allowed to cool to ambient temperature. The silica-alumina was removed via filtration through a 1-micron glass-fiber disc (the recovered solid was washed with EtOAc and then dried in a 50 C. oventhe material was recycled and subjected to the reaction conditions again, showing no appreciable loss of activity). The filtrate was concentrated under reduced pressure using a rotary evaporator. The crude material was then Kugelrohrdistilled at 1 mm Hg/150 C. to afford pure 2,2-(1,3-phenylene)dipropanal [6]. GC-MS t.sub.R: 14.47 min (Exact mass: 190.10 m/z, found: 190.1 m/z).

(23) This procedure was repeated at 100 C. with 100 g of diepoxide [4], 300 mL of toluene, and 25 g of SiAl Grade 135 with no change in conversion or appearance of change in activity.

(24) This procedure was repeated at 100 C. with 100 g of diepoxide [4], 400 mL of toluene, and 10 g of SiAl Grade 135 with no change in conversion or appearance of change in activity.

(25) The procedure was repeated at 100 C. with 100 g of diepoxide [4], 400 mL of toluene, and 5 g of SiAl Grade 135 with no change in conversion or appearance of change in activity.

(26) GC-MS Instrument ParametersAgilent 6890N GC with Agilent 5975B VL MSD

(27) Sample Prep: 100 L sample diluted to 1 mL with toluene; Column: DB-5 30 m0.25 mm0.25 m; Oven Ramp: 0-4.5 mins at 40 C.; Ramp 20 C/min to 280 C, Hold 53.5 mins; Injector: Temperature250 C.; Split Flow65 mL/min; Carrier Flow Rate1.3 mL/min; Volume1.0 L; MS: Transfer Line280 C.; Ion Source Temp230 C.; Mass Range34-700 amu.

(28) The invention has been described in detail with reference to the embodiments disclosed herein, but it will be understood that variations and modifications can be effected within the spirit and scope of the invention.