BE626870A - modified glycerides - Google Patents

Description

  

   <Desc / Clms Page number 1>
    



     Modified glycerides.



   The present invention relates to non-cyclic xylitol esters.



   It is known that esters of higher fatty acids with polyalcohols form a class of surfactant products. nonionic agents. In particular, they are used as emulsifying agents for oils and fats. This class of products includes, for example, monoesters and polyesters.

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 of lauric, palmitic, stearic, civic, summer acids, with ethylene glycol, glycerol, sorbitol, mannitol and pentadrythritol. In the case where the number of carbon atoms in the polyvalent alcohol chain and their molecular configuration allow the elimination of one or two molecules of water, with the formation of oxygen bridges,

     the end result of the esterification is a product of the partial esterification of fatty acids with mono-anhydro and dianhydro derivatives of polyvalent alcohols. Due to their very poor solubility in water, the application of the products described above is subject to certain limitations *
In addition, these products have a certain degree of toxicity so that their use as additives for foodstuffs is not advisable, especially at high doses.



   The applicant has found that it is possible to prepare special esters of fatty acids having 6 to 30 carbon atoms with xylitol, i.e. a polyalcohol. containing a straight chain with 5 carbon atoms which, because of its molecular configuration and the sufficient number of hydroxyl groups, has the property of giving two anhydrous derivatives, i.e. anhydro-xylitol and
1.4:

  2,5-dianhydro-xylitol. Thanks to the process described in the present patent, the final products obtained are mono-esters and diesters of fatty acids with xylitol, in which the latter is present in the non-cyclic form, that is to say. say that all hydroxyl groups are free, except of course those which are esterified with the fatty acid with which the xylitol has been reacted. The products thus obtained have a very high degree of surface activity, a very high activity of dispersion and emulsification, and they surprisingly show a much lower toxicity, so that they can be used even in high doses. as additives for foodstuffs.

   The process of the present patent comprises reacting one mole of a lower alkyl ester of a fatty acid having 6 to 30 carbon atoms, with 3 or more moles of xylitol, using a solvent of the class comprising dimethylformamide and dimethyl-

 <Desc / Clms Page number 3>

 
 EMI3.1
 tallow oxidizes, and allowing the reaction to develop in un'3 at.o ,.



  C ,,. Nitrogen phbre, at a temperature between 90 and 100 ° C, at a pressure of 250 to 300 mm Hg, for a period of 12 to 24 hours3, in the presence of an alkaline catalyst. After re ± rod1, s $ etï.c1 "l. ' the mixture is shaken with hexane causing the unreacted xylitol to stir up unreacted xylitol The xylitol is filtered off and the filtrate is concentrated to to dryness, the! '4 ::,' / being recrystallized from a suitable solvent, for example from dichloroethane.



    EXAMPLE 1.-
A mixture of 912 g of xylitol (6 moles), 540 g of
 EMI3.2
 Methylt palmitate (2 moles), 3,000 g of dimethylfor :: arnide and 27 g of potassium carbonate is heated for 12 hours: 3, -.



    92-95 C at a pressure of 250 mm Hg in a nitrogen atmosphere. After removing the dimethylformamide by distillation under
 EMI3.3
 empty, the residue is dissolved in butanol and cyclohexnne and the solution is washed with water to recover the excess xylitol.



  The solvents are removed and the residue is crystallized from ethyl acetate or dichloroethane. A production of 540 g of product is obtained having the following properties: r
 EMI3.4
 
<tb> <SEP> index of <SEP> saponification <SEP>: <SEP> 152.1
<tb>
<tb> Hydroxyl index <SEP> <SEP>: <SEP> 456.2
<tb>
<tb> Palmitic acid <SEP> <SEP>: <SEP> 1.56%
<tb>
<tb> Methyl <SEP> Palmitate <SEP> <SEP>: <SEP> 1.25%
<tb>
<tb> Humidity <SEP>: <SEP> 0.18%
<tb>
<tb> Mono-ester <SEP>: <SEP> 63 <SEP>%
<tb>
<tb> Diester <SEP>: <SEP> 37 <SEP>%
<tb>
 
The high hydroxyl number shows that the product is not in a cyclic form.



  EXAMPLE 2. -
A mixture of 456 g of xylitol (3 moles), 270 g of
 EMI3.5
 methyl palmitate (1 mole), 912 g of dimethylsulfide and

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 13.5 g of potassium carbonate is heated for 12 hours at 92-94 C under a pressure of 250 mm Hg in a nitrogen atmosphere. After removing the dimethylsulfoxide by vacuum distillation, the residue is dissolved in butanol and cyclohoxane. The solution is washed with water to recover the excess xylitol and it is evaporated to dryness.

   The residue is crystallized from ethyl acetate or dichloroethane. A production of 300 g of a product is obtained which has the following properties;
 EMI4.1
 
<tb> <SEP> index of <SEP> saponification <SEP>; <SEP> 154.3
<tb>
<tb>
<tb>
<tb> Hydroxyl index <SEP> <SEP>; <SEP> 457.1
<tb>
<tb>
<tb>
<tb>
<tb> Palmitic acid <SEP> <SEP>: <SEP> 1.42%
<tb>
<tb>
<tb>
<tb>
<tb> Methyl <SEP> Palmitate <SEP> <SEP>: <SEP> 1.31%
<tb>
<tb>
<tb>
<tb>
<tb> Humidity <SEP>: <SEP> 0.27%
<tb>
<tb>
<tb>
<tb>
<tb> Monoester <SEP> t <SEP> 63.05%
<tb>
<tb>
<tb>
<tb>
<tb> Diester <SEP>: <SEP> 36.5%
<tb>
 

** ATTENTION ** end of DESC field can contain start of CLMS **.

 

Claims (1)

CLAIMS- 1. A process for the preparation of non-cyclic, surfactant xylitol esters with fatty acids containing 6 to 30 carbon atoms, which comprises reacting in a solvent of the class comprising dimethylformamide and dimethylsulfoxide, of a lower alkyl ester of a fatty acid containing 6 to 30 carbon atoms, with at least 3 equimolecular amounts of xylitol, in the presence of an alkaline catalyst and in a nitrogen atmosphere, at a temperature of 90-100C, under a pressure of 250-300 mm Hg, for 12-24 hours, treating the reaction mass obtained with hexane, removing unreacted xylitol by filtration, removing the solvent by distillation, and recrystallizing the residue from a solvent. <Desc / Clms Page number 5> of 2. A process for the preparation of non-ring, surfactant, non-cyclic xylitol esters with fatty acids containing 6 to 30 atoms of carbon which comprises reacting in a cias solvent. EMI5.1 comprising dlm6tnylformamlde and d.m6thy7.au, toxyà :, ("a lower alkyl ester of a fatty acid containing 6:30 in situ" - 1; 1-, carbon, with at least 3 equimolar amounts of 7sy , it>: ', an' presence of potassium carbonate and in an atmosphere el '0.?', otc, at a temperature of 90 - 100 C, under a pressure of 230 to 300 - Hg for 12 to 24 hours, treatment of the mass of xc3 ^ r, <obtained with hexane, removal by filtration of unreacted xylitel, removal of the solvent by distillation and recrystallization of the residue from dichloroethane 3. A process according to claim 1, wherein the fatty acid lower alkyl ester is methyl palmitate 4. A process according to claim 1, wherein the lower alkyl fatty acid ester is methyl oleate. 5. A process according to claim 1, wherein the lower alkyl ester of fatty acid is methyl laurate, 6. A water soluble emulsifying agent consisting of the reaction product of xylitol with fatty acids containing 6 to 30 carbon atoms, when prepared according to the process of any preceding claim. . 7. Non-cyclic xylitol esters, with fatty acids containing 6 to 30 carbon atoms. 8. Non-cyclic xylitol moncypalmitate and dipalmitate. 9. Non-cyclic xylitol mono-oleate and dioleate. 10. Non-cyclic xylitol mono-laurate and dilaurate.