Patent Application
20070049763
This invention relates to a process for preparation and application of a novel strong base catalyst. The strong base is useful in conversion of conjugated linoleic acid (CLA) from alkyl esters of C1-C5 alkanols derived from oils rich in linoleic acid and conjugated linolenic acids from alkyl esters of C1-C5 alkanols derived from oils rich in linolenic acid. The reaction with alkyl esters of linoleic acid produces approximately equal amounts of the CLA isomers 9Z,11E-octadecadienoic acid and 10E,12Z-octadecadienoic acid. The reaction with alfa-linolenic acid produces a mixture of 9,13,15 Z,E,Z-octadecatrienoic acid, 9,11,15-Z,E,Z-octadecatrienoic acid and 10,12,14-E,Z,E-octadecatrienoic acid The reaction is unique in the reaction proceeds rapidly at temperatures as low as 20° C. and requires only catalytic amounts of the strong base and polyether alcohol.
In synthetic organic chemistry base catalysts may be divided into classes of base strength. Depending on the base strength different catalyzed reactions are possible with each class of base. Metal carbonates and hydroxides such as sodium and potassium hydroxide are efficient catalysts for transesterification and have been used to produce sucrose polyesters and alkyl esters. Strong base catalysts such as metal alkoxides (egs. Sodium methylate, potassium tertiary butryate) are broadly used in commercial organic syntheses and often preferred in specific reactions. The strong bases are often capable of catalyzing reactions at lower temperatures and in less expensive solvent systems. While some of these bases are prone to oxidation all are prone to inactivation by reaction with water.
Conjugated linoleic acid is the trivial name given to a series of eighteen carbon diene fatty acids with conjugated double bonds. Applications of conjugated linoleic acids vary from treatment of medical conditions such as anorexia (U.S. Pat. No. 5,430,066) and low immunity (U.S. Pat. No. 5,674,901) to applications in the field of dietetics where CLA has been reported to reduce body fat (U.S. Pat. No. 5,554,646) and to inclusion in cosmetic formulae (U.S. Pat. No. 4,393,043). CLA shows similar activity in veterinary applications. In addition, CLA has proven effective in reducing valgus and varus deformity in poultry (U.S. Pat. No. 5,760,083), and attenuating allergic responses (U.S. Pat. No. 5,585,400). CLA has also been reported to increase feed conversion efficiency in animals (U.S. Pat. No. 5,428,072). CLA-containing bait can reduce the fertility of scavenger bird species such as crows and magpies (U.S. Pat. No. 5,504,114).
Industrial applications for CLA also exist where it is used as a lubricant constituent (U.S. Pat. No. 4,376,711). CLA synthesis can be used as a means to chemically modify linoleic acid so that it is readily reactive to Diels-Alder reagents (U.S. Pat. No. 5,053,534). In one method linoleic acid was separated from oleic acid by first conjugation then reaction with maleic anhydride followed by distillation (U.S. Pat. No. 5,194,640).
Conjugated linoleic acid occurs naturally in ruminant depot fats. The predominant form of CLA in ruminant fat is the 9Z,11E-octadecadienoic acid which is synthesized from linoleic acid in the rumen by micro-organisms like Butryvibrio fibrisolvens. The level of CLA found in ruminant fat is in part a function of dietary 9Z,12Z-octadecadienoic acid and the level of CLA in ruminant milk and depot fat may be increased marginally by feeding linoleic acid (U.S. Pat. No. 5,770,247).
CLA may also be prepared by any of several analytical and preparative methods. Pariza and Ha pasteurized a mixture of butter oil and whey protein at 85° C. for 5 minutes and noted elevated levels of CLA in the oil (U.S. Pat. No. 5,070,104). CLA produced by this mechanism is predominantly a mixture of 9Z,11E-octadecadienoic acid and 10E,12Z-octadecadienoic acid. CLA has also been produced by the reaction of soaps with strong alkali bases in molten soaps, alcohol, and ethylene glycol monomethyl ether (U.S. Pat. Nos. 2,389,260; 2,242,230 & 2,343,644). These reactions are inefficient, as they require the multiple steps of formation of the fatty acid followed by production of soap from the fatty acids, and subsequently increasing the temperature to isomerize the linoleic soap. The CLA product is generated by acidification with a strong acid (sulfuric or hydrochloric acid) and repeatedly washing the product with brine or CaCl2.
Iwata et al. (U.S. Pat. No. 5,986,116) overcame the need for an intermediate step of preparation of fatty acids by reacting oils directly with alkali catalyst in a solvent of propylene glycol under low water or anhydrous conditions. Reaney et al. (Reaney, Liu and Westcott (1999) Commercial production of CLA. In Yurawecz, Mossaba, Kramer, Pariza and Nelson Eds. Advances in conjugated linoleic acid research, Vol. 1 pp.) identified that CLA products prepared in the presence of glycol and other alcohols may transesterify with the glycerol and produce esters of the glycol. Such esters have been identified by Reaney (unpublished work) in commercial products and in CLA prepared in propylene glycol by the method of U.S. Pat. No. 5,986,116. The biological activity of esters of CLA containing fatty acids and propylene glycol is relatively high and therefore their presence in the CLA product is undesirable.
CLA has been synthesized from fatty acids using SO2 in the presence of a sub-stoichiometric amount of soap forming base (U.S. Pat. No. 4,381,264). The reaction with this catalyst produced predominantly the all trans configuration of CLA.
Baltes, Wechmann and Weghorst (U.S. Pat. No. 3,162,658) achieved the conjugation of distilled methyl esters of soybean oil by the addition of 10 percent potassium methylate at 120° C. in five hours. The reaction produced 97% conjugation of the available double bonds.
Ritz and Reese (U.S. Pat. No. 3,984,444) found that aprotic solvents were suitable for the formation of conjugated bonds in soybean oil. They report mixing 500 g of soy oil with 500 g of DMSO at 50° C. and then adding 5 grams of finely divided potassium methylate. The reaction produced 97% conjugation of the available double bonds
Efficient synthesis of 9Z,11E-octadecadienoic from ricinoleic acid has been achieved (Russian Patent 2,021,252). This synthesis, although efficient, uses expensive elimination reagents such as 1,8-diazobicyclo-(5,4,0)-undecene. For most applications the cost of the elimination reagent increases the production cost beyond the level at which commercial production of CLA is economically viable.
Of these methods alkali isomerization of soaps is the least expensive process for bulk preparation of CLA isomers, however, the use of either monohydric or polyhydric alcohols in alkali isomerization of CLA can be problematic. Lower alcohols are readily removed from the CLA product but they require the production facility be built to support the use of flammable solvents. Higher molecular weight alcohols and polyhydric alcohols are considerably more difficult to remove from the product and residual levels of these alcohols (e.g. ethylene glycol) may not be acceptable in the CLA product.
Water may be used in place of alcohols in the production of CLA by alkali isomerization of soaps (U.S. Pat. Nos. 2,350,583 and 4,164,505). When water is used for this reaction it is necessary to perform the reaction in a pressure vessel whether in a batch (U.S. Pat. No. 2,350,583) or continuous mode of operation (U.S. Pat. No. 4,164,505). The process for synthesis of CLA from soaps dissolved in water still requires a complex series of reaction steps. Bradley and Richardson (Industrial and Engineering Chemistry February 1942 vol 34 no 2 237-242) were able to produce CLA directly from soybean triglycerides by mixing sodium hydroxide, water and oil in a pressure vessel. Their method eliminated the need to synthesize fatty acids and then form soaps prior to the isomerization reaction. However, they reported that they were able to produce oil with up to 40 percent CLA. Quantitative conversion of the linoleic acid in soybean oil to CLA would have produced a fatty acid mixture with approximately 54 percent CLA.
In order to overcome the high cost of alkali and solvent often encountered in CLA production Reaney (U.S. Pat. No. 6,409,649) developed a method for utilizing the waste alkaline glycerol from biodiesel synthesis as a catalyst and medium for CLA production. Similarly Reaney (U.S. Pat. No. 6,414,171) describe the direct conversion of soapstock from the alkaline treatment of vegetable oils to CLA. This conversion has the advantage of using water as the reaction medium and the presence of large amounts of alkali in the soap. Though inexpensive, both reactions require heating the reaction mixture to temperatures above 190° C.
Commercial conjugated linoleic acid often contains a mixture of positional isomers that may include 8E,10Z-octadecadienoic acid, 9Z,11E-octadecadienoic acid, 10E,12Z-octadecadienoic acid, and 11Z,13E-octadecadienoic acid (Christie, W. W., G. Dobson, and F. D. Gunstone, (1997) Isomers in commercial samples of conjugated linoleic acid. J. Am. Oil Chem. Soc. 74, 11, 1231).
The present invention describes a method of production of CLA using polyethylene glycol alone or with a co-solvent as a reaction medium and a vegetable oil containing more than 60% linoleic acid. The reaction products in polyether glycol containing solvent are primarily 9Z,11E-octadecadienoic acid and 10E,12Z-octadecadienoic acid in equal amounts. The reaction product is readily released by acidification.
In the present invention a strong base solution is prepared which is suitable for catalyzing numerous reactions. The strong base is produced by the mixture of simple commercially available starting materials including both alkali hydroxide base and a polyether alcohol solvent. When this mixture is heated under vacuum a reaction takes place wherein water is released and viscosity rises. Surprisingly the product of this reaction is an unusually powerful base that has advantageous properties in chemical synthesis using base catalyst. The strong base is non-volatile and non-toxic. It has greater potency than many conventional strong base solutions as the ether alcohol solvents act as a phase transfer solvent to assist in the reaction.
Thus, by one aspect of the invention there is provided a process for producing a polyethylene alkylate catalyst comprising reacting an alkali base, selected from the group consisting of hydroxide, alkoxide, metal and hydride, with a polyether alcohol solvent, under vacuum at a temperature in the range of 100° C.-150° C., so as to produce a non volatile, non toxic polyether alkylate catalyst.
By another aspect of this invention there is provided a strong base catalyst composition comprising a non volatile, non toxic polyether alkylate produced by reaction between an alkali base, selected from the group consisting of hydroxide, alkoxide, metal and hydride, and polyether alcohol.
By yet another aspect of this invention there is provided a process for producing an isomeric conjugated linoleic acid (CLA)-rich alkyl ester mixture comprising reacting a linoleic acid-rich oil in the presence of a catalytic amount of a strong base comprising a non volatile non toxic polyether alkylate at a temperature above 50° C. and separating said CLA-rich alkyl ester mixture.
In the current art a strong base catalyst is produced by the reaction of a weaker base with a polyether alcohol using the art of the present invention to greatly increase the activity of the base. In a preferred process the base of the current invention is prepared by dissolving an amount of alkali hydroxide of a Group I alkali earth metal in the polyether alcohol and then heating the mixture under vacuum (
The polyether alcohol is chosen because of its low toxicity, its stability during storage and its ready ability to form an alkoxide by reaction with base. Once formed the polyether alcohol base can be used in a number of reactions to displace alkoxides of the lower alcohols in similar applications.
Formation of the catalyst may be determined by the loss of water, alcohol or hydrogen depending on the source of base used in catalyst synthesis. The accurate measurement mass loss during the synthesis can indicate the formation of the catalyst. The production of the catalyst increases the viscosity of the catalyst solution in polyether alcohol. Furthermore, the catalyst can be identified by changes both the IR and NMR spectrum of the solution. Using combined analytical methods it may be shown that the catalyst produced by reaction of aqueous alkali hydroxide solution, solid alkali hydroxide, alkoxide of lower alcohol and metal were equivalent in chemical composition.
It is known by those skilled in the art that the strength of alkoxide catalysts may be affected by the nature of the alcohol. It is known, for example, that primary alcohols such as ethanol form weaker base than do tertiary alcohols like tertiary butanol. The current art includes bases made from polyether alcohols that contain primary, secondary and tertiary alcohols.
The catalyst is also characterized by its unique ability to facilitate difficult chemical reactions under mild conditions. In a preferred reaction the catalyst was utilized to conjugate the fatty alkyl esters of a linoleic acid rich oil to form conjugated linoleic acid. The conditions of this reaction are mild and produce and advantageous isomer mixtures. Reaction progress in determining the efficacy of the catalyst was determined by gas liquid chromatography and NMR spectroscopy.
Hydroxides of lithium, sodium, potassium, rubidium (solution) and cesium (monohydrate) were placed in round bottom flasks and heated to 110° C. in a vacuum oven under vacuum (29″) for 1 hour. With the exception of the rubidium hydroxide in solution there was no appreciable weight change. The rubidium solution lost a small amount of water. The color of the hydroxides remained constant with the treatment. Similarly polyethylene glycol 300 MW was placed in a round bottomed flask at the same time under vacuum. The peg solution remained clear and colorless throughout the treatment. The flasks were then removed from the heat and vacuum sources and the weight of the flask recorded. There was no change in weight of the solution. The infrared spectrum of the PEG and the PEG alkylates were recorded on samples placed between KBr salt blocks both before and after the vacuum treatment. The NMR spectra of the PEG and the PEG alkylates were recorded on samples both before and after treatment. The spectra of the untreated and treated materials were highly similar. Vacuum treatment alone did not change the composition of the PEG solution.
To each flask containing a metal hydroxide was added 10 times the weight of PEG 300. The flasks were placed in the vacuum oven at room temperature and the temperature was raised slowly to 110° C. All of the solutions boiled vigorously under the heat and vacuum treatment. All of the solutions turned to amber and then to dark brown. After vacuum treatment for 18 hours most boiling had ceased and no residual solid catalyst was present in the solutions of KOH, rubidium and cesium. Significant amounts of undissolved sodium catalyst remained in the bottom of the flask. The weight of each flask was recorded after the vacuum treatment. The FT-IR spectra of the basic solutions prepared under treatment with heat and vacuum were recorded by placing the samples between salt blocks. It was observed that each sample lost weight as would be consistent with the formation of an alkali metal alkoxide of the polyethylene glycol. The vacuum treatment substantially increased the viscosity of the PEG solution as well.
The FT-IR showed significant changes in peak absorbance. The primary difference was the lessening or disappearance of the hydroxyl absorbance at 3364 cm−1 (
Taken as a whole the weight loss on reaction and the disappearance of the IR and NMR peaks at 3364 cm−1 and 2.9 ppm respectively are consistent with the formation of PEG alkylate.
Two grams of a solution of 45% potassium hydroxide in water or two grams of a solution of 50% sodium hydroxide in water were added to 13 grams of polyethylene glycol 300 in a pre-weighed round bottom flask containing a Teflon coated stirring bar. The flask was equipped with a vacuum adaptor and heated to 130° C. under vacuum (0.01 mm Hg) with stirring until all bubbling ceased. The flask was then removed from the heat and vacuum sources and the weight of the flask recorded. The FT-IR spectra of the basic solutions were recorded by placing the samples between KBr windows.
Weight loss was recorded for PEG and each base separately and the weight loss of the reactants together was also determined. Weight loss of greater than the sum of the loss of the two separate ingredients was assumed to be due to formation of the strong base PEG alkylate catalyst with the concomitant loss of water. FT-IR showed a decrease in the characteristic OH stretch absorbance of PEG solutions observed at 3365 cm−1.
Either 0.95 g of sodium carbonate or 1.41 g of potassium carbonate were added to 13 grams of polyethylene glycol 300 in a pre-weighed round bottom flask containing Teflon coated stirring bar. The flask was equipped with a vacuum adaptor and heated to 130° C. under vacuum (0.01 mm Hg) until all bubbling ceased. The flask was then removed from the heat and vacuum sources and the weight of the flask recorded. The FT-IR spectra of the basic solutions were recorded by placing the samples between KBr windows.
Weight loss was recorded for PEG and each base separately and the weight loss of the reactants together was also determined. Weight loss was minor and it was assumed that the strong base metal alkylate catalyst did not form. FT-IR showed a no decrease in the characteristic OH stretch absorbance of PEG solutions at 3365 cm−1.
One gram of freshly prepared potassium ethoxide was added to 13 grams of polyethylene glycol 300 in a pre-weighed round bottom flask containing a Teflon coated stirring bar. The flask was equipped with a vacuum adaptor and heated to 130° C. under vacuum (0.01 mm Hg) until all bubbling ceased. The flask was then removed from the heat and vacuum sources and the weight of the flask recorded. The FT-IR spectra of the basic solutions were recorded by placing the samples between KBr windows.
Weight loss was recorded for PEG and potassium ethoxide separately and the weight loss of the reactants together was also determined. Weight loss of greater than the sum of the loss of the two separate ingredients was assumed to be due to formation of the PEG alkylate strong base catalyst with the concomitant loss of alcohol. FT-IR showed a similar decrease in the characteristic OH stretch absorbance of PEG solutions at 3365 cm−1 consistent with the formation of the catalyst.
Polyethylene glycol 300 (13 g) was added to a pre-weighed round bottom flask containing a Teflon coated stirring bar. The flask was equipped with a vacuum adaptor and heated to 130° C. under vacuum (0.01 mm Hg) until all bubbling ceased. The flask was then removed from the heat and vacuum sources and the weight of the flask recorded. Subsequently either 0.41 g of sodium or 0.70 g of potassium was added to the dry PEG. The FT-IR spectra of the basic solutions were recorded by placing the samples between KBr windows.
Weight loss was recorded for PEG and each base separately and the weight loss of the reactants together was also determined. Weight loss of greater than the sum of the loss of the two separate ingredients was assumed to be due to formation of the strong base catalyst with the concomitant loss of hydrogen. FT-IR showed a similar decrease in the characteristic OH stretch absorbance of PEG solutions at 3365 cm−1 consistent with the formation of the catalyst.
Potassium carbonate (1.41 g) and calcium hydroxide (0.66 g) were added to 13 grams of polyethylene glycol 300 in a preweighed round bottom flask containing a teflon coated stirring bar. The flask was equipped with a vacuum adaptor and heated to 130° C. under vacuum (0.01 mm Hg) until all bubbling ceased. The flask was then removed from the heat and vacuum sources and the weight of the flask recorded. The FT-IR spectra of the basic solutions were recorded by placing the samples between KBr windows.
Weight loss was recorded for PEG and each base separately and the weight loss of the reactants together was also determined. Weight loss of greater than the sum of the loss of the two separate ingredients was assumed to be due to formation of the strong base catalyst with the concomitant loss of alcohol. FT-IR showed a similar decrease in the characteristic OH stretch absorbance of PEG solutions at 3365 cm−1.
Potassium hydroxide (1.0 g) was added to 13 grams of each of several polyether alcohols in a preweighed round bottom flask containing a teflon coated stirring bar. The polyether alcohols included PEG 200, 300, 1500, 3000, Brij 92, Brij 72 and polypropylene glycol. The flask was equipped with a vacuum adaptor and heated to 130° C. under vacuum (0.01 mm Hg) until all bubbling ceased. The flask was then removed from the evaporator and the weight of the flask recorded. The FT-IR spectra of the basic solutions were recorded by placing the samples between KBr windows.
Weight loss was recorded for each polyether alcohol and each base separately and the weight loss of the reactants together was also determined. Weight loss of greater than the sum of the loss of the two separate ingredients was assumed to be due to formation of the strong base catalyst with the concomitant loss of water. FT-IR showed a similar decrease in the characteristic OH stretch absorbance of solutions between at 3365 cm−.
Methyl esters were prepared for other examples of strong base isomerization. Methyl ester of safflower oil was prepared by alkali catalyzed alcoholysis with methanol. The base alcohol catalysis solution was prepared by mixing 200 grams of methanol with 10 grams of potassium hydroxide in a covered glass beaker. Mixing of the solid hydroxide was facilitated by adding a Teflon coated magnet and placing the beaker on a stirrer hot plate. Once the mixture was dissolved 120 grams of the solution was transferred to 1000 grams of safflower oil. This mixture was agitated for 1 hour at room temperature using a Teflon coated bar magnet on a stirrer hotplate. After 1 hour the contents of the reaction vessel were transferred to a 2 liter glass separatory funnel and allowed to separate for 4 hours. After 4 hours the lower layer containing primarily glycerin was drained and set aside the upper layer was returned to a beaker for a second stage of reaction.
The second stage of reaction was accomplished by adding the remaining catalyst alcohol solution (90 g) to the safflower oil and agitating with a Teflon stirring bar as described above for 1 hour. The reaction contents were transferred to a 2 liter glass separatory funnel and allowed to separate overnight. After settling the lower layer containing glycerin, potassium hydroxide and alcohol was removed. The upper layer was placed on a rotary evaporator to substantially remove all remaining methanol. After the alcohol was removed the methyl ester was filtered on a glass fiber filter to remove residual glycerol catalyst and soaps. The residual material was used as a safflower oil methyl ester substrate in further reactions.
Ethyl ester of safflower oil was prepared by alkali catalyzed alcoholysis with ethanol. The base alcohol catalysis solution was prepared by mixing 350 grams of ethanol with 10 grams of potassium hydroxide in a covered glass beaker. Mixing of the solid hydroxide was facilitated by adding a Teflon coated magnet and placing the beaker on a stirrer hot plate. Once the mixture was dissolved it was transferred to 1000 grams of flax oil. This mixture was agitated for 2 hours at room temperature using a Teflon coated bar magnet on a stirrer hotplate. After 2 hours the contents of the reaction vessel were transferred to a 2 liter glass separatory funnel and allowed to separate for 4 hours. The lower layer containing glycerin unreacted ethanol and potassium hydroxide was removed. The upper layer was placed on a rotary evaporator to substantially remove all remaining ethanol. After the alcohol was removed the ethyl ester was filtered on a glass fiber filter to remove residual glycerol, catalyst and soaps. The residual material was used as a safflower oil ethyl ester substrate in further reactions.
Methyl ester of flax oil was prepared by alkali catalyzed alcoholysis with methanol. The base alcohol catalysis solution was prepared by mixing 200 grams of methanol with 10 grams of potassium hydroxide in a covered glass beaker. Mixing of the solid hydroxide was facilitated by adding a Teflon coated magnet and placing the beaker on a stirrer hot plate. Once the mixture was dissolved 120 grams of the solution was transferred to 1000 grams of flax oil. This mixture was agitated for 1 hour at room temperature using a Teflon coated bar magnet on a stirrer hotplate. After 1 hour the contents of the reaction vessel were transferred to a 2 liter glass separatory funnel and allowed to separate for 4 hours. After 4 hours the lower layer containing primarily glycerin was drained and set aside the upper layer was returned to a beaker for a second stage of reaction.
The second stage of reaction was accomplished by adding the remaining catalyst alcohol solution (90 g) to the safflower oil and agitating with a Teflon stirring bar as described above for 1 hour. The reaction contents were transferred to a 2 liter glass separatory funnel and allowed to separate overnight. After settling the lower layer containing glycerin, potassium hydroxide and alcohol was removed. The upper layer was placed on a rotary evaporator to substantially remove all remaining methanol. After the alcohol was removed the methyl ester was filtered on a glass fiber filter to remove residual glycerol catalyst and soaps. The residual material was used as a flax oil methyl ester substrate in further reactions.
One hundred grams of safflower methyl ester (prepared according to example 8) was added to 13 g of PEG potassium alkylate (prepared according to example 1) in a round bottom flask. A Teflon coated stirring bar was added to the flask to afford agitation. The flask was placed in a constant temperature bath and stirred while it was held at 110° C. Vacuum (27″) was applied to the flask through a condenser. The reaction mixture bubbled vigorously for the first minutes due to the release of methanol. After two hours the vacuum was released and a sample of the reaction mixture was taken and added to deuterated chloroform in an NMR sample tube. The 400 MHz NMR spectrum was recorded. It was found that the methylene interrupt signal normally found at 2.78 ppm was greatly diminished and that new signals attributable to conjugated lipids had appeared at 6.25, 5.90, and 5.60 ppm.
One hundred grams of safflower ethyl ester (prepared according to example 9) was added to 13 g of PEG potassium alkylate (prepared according to example 2) in a round bottom flask. A Teflon coated stirring bar was added to the flask to afford agitation. The flask was placed in a constant temperature bath and stirred while it was held at 110° C. Vacuum (27″) was applied to the flask through a condenser. The reaction mixture bubbled vigorously for the first minutes due to the release of methanol. After two hours the vacuum was released and a sample of the reaction mixture was taken and added to deuterated chloroform in an NMR sample tube. The 400 MHz NMR spectrum was recorded. It was found that the methylene interrupt signal normally found at 2.78 ppm was greatly diminished and that new signals attributable to conjugated lipids had appeared at 6.25, 5.90, and 5.60 ppm.
One hundred grams of safflower ethyl ester (prepared according to example 9) was added to 13 g of PEG potassium carbonate in a round bottom flask. A Teflon coated stirring bar was added to the flask to afford agitation. The flask was placed in a constant temperature bath and stirred while it was held at 110° C. Vacuum (27″) was applied to the flask through a condenser. The reaction mixture bubbled vigorously for the first minutes due to the release of methanol. After two hours the vacuum was released and a sample of the reaction mixture was taken and added to deuterated chloroform in an NMR sample tube. The 400 MHz NMR spectrum was recorded. It was found that the methylene interrupt signal normally found at 2.78 ppm was not altered by the treatment. This is consistent with the observation that no PEG alkylate catalyst formed using the metal carbonate as a source of base.
One hundred grams of safflower ethyl ester (prepared according to example 9) was added to 13 g of PEG potassium alkylate (prepared according to example 4) in a round bottom flask. A Teflon coated stirring bar was added to the flask to afford agitation. The flask was placed in a constant temperature bath and stirred while it was held at 110° C. Vacuum (27″) was applied to the flask through a condenser. The reaction mixture bubbled vigorously for the first minutes due to the release of methanol. After two hours the vacuum was released and a sample of the reaction mixture was taken and added to deuterated chloroform in an NMR sample tube. The 400 MHz NMR spectrum was recorded. It was found that the methylene interrupt signal normally found at 2.78 ppm was greatly diminished and that new signals attributable to conjugated lipids had appeared at 6.25, 5.90, and 5.60 ppm.
One hundred grams of safflower ethyl ester (prepared according to example 9) was added to 13 g of PEG potassium alkylate (prepared according to example 4) in a round bottom flask. A Teflon coated stirring bar was added to the flask to afford agitation. The flask was placed in a constant temperature bath and stirred while it was held at 110° C. Vacuum (27″) was applied to the flask through a condenser. The reaction mixture bubbled vigorously for the first minutes due to the release of methanol. After two hours the vacuum was released and a sample of the reaction mixture was taken and added to deuterated chloroform in an NMR sample tube. The 400 MHz NMR spectrum was recorded. It was found that the methylene interrupt signal normally found at 2.78 ppm was greatly diminished and that new signals attributable to conjugated lipids had appeared at 6.25, 5.90, and 5.60 ppm.
Twenty five grams of safflower ethyl ester (prepared according to example 9) was added to 13 g of PEG cesium alkylate (prepared according to example 1) in a round bottom flask. A Teflon coated stirring bar was added to the flask to afford agitation. The flask was placed in a constant temperature bath and stirred while it was held at 110° C. Vacuum (27″) was applied to the flask through a condenser. The reaction mixture bubbled vigorously for the first minutes due to the release of methanol. After two hours the vacuum was released and a sample of the reaction mixture was taken and added to deuterated chloroform in an NMR sample tube. The 400 MHz NMR spectrum was recorded. It was found that the methylene interrupt signal normally found at 2.78 ppm was greatly diminished and that new signals attributable to conjugated lipids had appeared at 6.25, 5.90, and 5.60 ppm.
Twenty five grams of safflower ethyl ester (prepared according to example 9) was added to 3.25 g of PEG rubidium alkylate (prepared according to example 1) in a round bottom flask. A Teflon coated stirring bar was added to the flask to afford agitation. The flask was placed in a constant temperature bath and stirred while it was held at 110° C. Vacuum (27″) was applied to the flask through a condenser. The reaction mixture bubbled vigorously for the first minutes due to the release of methanol. After two hours the vacuum was released and a sample of the reaction mixture was taken and added to deuterated chloroform in an NMR sample tube. The 400 MHz NMR spectrum was recorded. It was found that the methylene interrupt signal normally found at 2.78 ppm had disappeared and that new signals attributable to conjugated lipids had appeared at 6.25, 5.90, and 5.60 ppm.
One hundred grams of flax methyl ester (prepared according to example 8) was added to 13 g of PEG potassium alkylate (prepared according to example 1) in a round bottom flask. A Teflon coated stirring bar was added to the flask to afford agitation. The flask was placed in a constant temperature bath and stirred while it was held at 110° C. Vacuum (27″) was applied to the flask through a condenser. The reaction mixture bubbled vigorously for the first minutes due to the release of methanol. After two hours the vacuum was released and a sample of the reaction mixture was taken and added to deuterated chloroform in an NMR sample tube. The 400 MHz NMR spectrum was recorded. It was found that the methylene interrupt signal normally found at 2.78 ppm was greatly diminished and that a complex pattern of new signals attributable to conjugated lipids had appeared between 5.5 and 6.5 ppm.
Tetramethyl ammonia hydroxide (488 mg) and PEG 300 (3.0 g) were mixed in a round bottom flask under vacuum at 110° C. for 2 hours. Twenty five grams of safflower ethyl ester (prepared according to example 9) was added to 3.25 g of the PEG tetramethyammonium alkylate in the flask. A Teflon coated stirring bar was added to the flask to afford agitation. The flask was placed in a constant temperature bath and stirred while it was held at 110° C. Vacuum (27″) was applied to the flask through a condenser. The reaction mixture bubbled vigorously for the first minutes due to the release of methanol. After two hours the vacuum was released and a sample of the reaction mixture was taken and added to deuterated chloroform in an NMR sample tube. The 400 MHz NMR spectrum was recorded. It was found that the methylene interrupt signal normally found at 2.78 ppm had disappeared and that new signals attributable to conjugated lipids had appeared at 6.25, 5.90, and 5.60 ppm.
One hundred grams of safflower methyl ester (prepared according to example 8) was added to 13 g of polypropylene glycol potassium alkylate (prepared according to example 7) in a round bottom flask. A Teflon coated stirring bar was added to the flask to afford agitation. The flask was placed in a constant temperature bath and stirred while it was held at 110° C. Vacuum (27″) was applied to the flask through a condenser. The reaction mixture bubbled vigorously for the first minutes due to the release of methanol. After two hours the vacuum was released and a sample of the reaction mixture was taken and added to deuterated chloroform in an NMR sample tube. The 400 MHz NMR spectrum was recorded. It was found that the methylene interrupt signal normally found at 2.78 ppm was greatly diminished and that new signals attributable to conjugated lipids had appeared at 6.25, 5.90, and 5.60 ppm.
