Method of producing 11(e)-tetradecen-1-ylacetate

FIELD: chemistry.

SUBSTANCE: invention relates to an improved method of producing 11(E)-tetradecen-1-ylacetate, which is sex pheromone of sod webworms, the basic component of pheromones of omnivorous leaf-roller moths, stem moths, fir leaf-roller moths and certain other types of dangerous pests, involving a Grignard reaction of acrolein with ethylmagnesium bromide to obtain 1-penten-3-ol, ortho-ether Claisen rearrangement with participation of 1-penten-3-ol and triethyl ortho-acetate to obtain ethyl ether of 4(E)-heptenoic acid, reduction of the ethyl ether of 4(E)-heptenoic acid to obtain 4(E)-hepten-1-ol, substitution of the hydroxyl group of 4(E)-hepten-1-ol with Br to obtain 1-bromo-4(E)-heptene, cross-coupling reaction of 1-bromo-4(E)-heptene with 7-[(tetrahydro-2H-pyran-2-yl)oxy]heptylmagnesium bromide in the presence of a catalyst to obtain 11(E)-tetradecen-1-ol, acetylation of 11(E)-tetradecen-1-ol to obtain 11(E)-tetradecen-1-ylacetate, in which cross-coupling of 1-bromo-4(E)-heptene with 7-[(tetrahydro-2H-pyran-2-yl)oxy]heptylmagnesium bromide to obtain 11(E)-tetradecen-1-ol is carried out in the presence of a Li2CuCl4 in the medium of tetrahydrofuran in the following molar ratio [1-bromo-4(E)-heptene]: [7-[(tetrahydro-2H-pyran-2-yl)oxy]heptylmagnesium bromide]:[ Li2CuCl4]:[tetrahydrofuran]=1:1.2:0.03:20 for 1 hour at temperature of minus 75°C, then for 1 hour at temperature ranging from minus 75°C to 20°C and for 10 hours at 20°C. Since the 1-2% content of the (Z)-isomer already inhibits attractive properties of 11(E)-tetradecen-1-ylacetate, existing methods are not suitable for practical application.

EFFECT: method is distinguished by stereoselectivity.

2 ex

 

The invention relates to the field of organic chemistry, in particular to a method for 11(E)-tetradeca-1-racette.

11(E)-Tetradeca-1-ylacetic is the sex pheromone of the meadow moth (Loxostege sticticalis), the main component of the pheromone omnivorous leafroller (Archips podana), stem borer (Ostrinia nubilalis), spruce leafroller (Choristoneura fumiferana) and some other types of dangerous pests.

A method of obtaining 11(E)-tetradeca-1-ilaclama (..Sonnet, J.E.Oliver, J. Org. Chem., 1976, vol.41, No. 20, p.3279-3283), based on the inversion of the double bond (Z)-isomer. The method consists of epoxydecane (11Z)-tetradecene-1-racette, the reaction of the epoxide with triphenylphosphonium and recovering the resulting dihalogenide activated zinc. The method is based on the difficult and costly (11Z)-tetradecene-1-racette and has a low selectivity.

A method of obtaining 11(E)-tetradeca-1-ilaclama (I.Toshinobu, Y.Akira, .Kenichi, patent JP 57024326, 1982), based on the isomerization of 11(Z)-tetradeca-1-racette in the presence of metallic selenium. The method is based on the difficult and costly 11(Z)-tetradeca-1-racemate and is characterized by low selectivity (E/Z=1.48).

Because of 1-2%, the content of (Z)-isomer inhibits invasive properties 11(E)-tetradeca-1-racette, both methods are unsuitable for practical application.

Select the ing us for the prototype method for producing 11(E)-tetradeca-1-ilaclama (1) (Rnewman, Auesbaeva, Issacharoff, Stereoselective synthesis of 11(E)-tetradeca-1-ilaclama - sexual pheromone meadow moth (Loxostege sticticalis), Joh, 2009, t, issue 6, s-1002) based on available and cheap raw materials (acrolein), high stereoselectivity and includes the following stages:

1. the Grignard reaction of acrolein (2) ethylmagnesium obtaining 1-penten-3-ol (3);

2. orthoevra rearrangement of Clausena involving 1-penten-3-ol (3) and triethylorthoformate with obtaining the ethyl ester 4(E)-heptenophos acid (4);

3. recovery ethyl ester 4(E)-heptenophos acid (4) Litia-luminosidade obtaining 4(E)-hepten-1-ol (5);

4. bromination of 4(E)-hepten-1-ol (5) complex PPh3·Br2to obtain 1-bromo-4(S)-Heptene (6);

5. the reaction cross-combination of 1-bromo-4(S)-Heptene (6) 7-[(tetrahydro-2H-Piran-2-yl)oxy]heptylaniline (7) in the presence of a catalytic system CuI-2,2'-bipyridyl with getting 11(E)-tetradecene-1-ol (8);

6. acetylation 11(E)-tetradecene-1-ol (8) a mixture of AU2O/Ru obtaining 11(E)-tetradeca-1-ilaclama (1).

a. EtMgBr; b. CH3C(OEt)3CH3COOH; C. LiAlH4d. PPh3-Br2; that is, THPO (CH2)7MgBr (7), CuI/2,2'-bipy; f. MeOH/TsOH; g. AU2O/Ru.

The overall yield of 11(E)-tetradeca-1-racette on the source acrolein is 33.5%, per 1-b the om-4(E)-hepten - 63%.

The method has significant drawbacks at the stage of cross-combination of 1-bromo-4(S)-Heptene with 7-[(tetrahydro-2H-Piran-2-yl)oxy]heptylene-bromide:

1. The use of expensive and highly toxic catalyst is 2,2'-bipyridyl and high rates of consumption (not less than 0.2 mol per 1 mol of 1-bromo-4(S)-Heptene). For this reason, this process is-low-tech and is of only theoretical interest.

2. The low yield of product.

The objective of the invention is to provide a cheaper and safer way to obtain 11(E)-tetradeca-1-ilaclama with higher output.

This task is solved in that in the method of obtaining 11(E)-tetradeca-1-racette, including the reaction of Grignard acrolein with ethylmagnesium obtaining 1-penten-3-ol, artevino the klaisen rearrangement involving 1-penten-3-ol and triethylorthoformate with obtaining the ethyl ester 4(E)-heptenophos acid, recovery of the ethyl ester 4(E)-heptenophos acid to obtain 4(E)-hepten-1-ol, substitution of the hydroxyl group of 4(E)-hepten-1-ol Br to obtain 1-bromo-4(S)-Heptene, reaction cross-combination of 1-bromo-4(S)-Heptene with 7-[(tetrahydro-2H-Piran-2-yl)oxy]heptylaniline in the presence of the catalyst 11(E)-tetradecene-1-ol, acetylation 11(E)-tetradecene-1-ol with getting 11(E)-tetradeca-1-racette, according to izaberete the Oia, cross-coupling of 1-bromo-4(S)-Heptene with 7-[(tetrahydro-2H-Piran-2-yl)oxy]heptylaniline with getting 11(E)-tetradecene-1-ol is carried out in the presence of a catalyst Li2CuCl4in the medium of anhydrous tetrahydrofuran in the following molar ratio [1-bromo-4(E)-hepten]:[7-[(tetrahydro-2H-Piran-2-yl)oxy]heptylaniline]:[Li2CuCl4]:[tetrahydrofuran]=1:1.2:0.03:20 for 1 h at a temperature of minus 75°C., then for 1 h at the temperature of minus 75°C to 20°C and for 10 h at 20°C.

The method is as follows. A mixture of 1-bromo-4(S)-Heptene, 7-[(tetrahydro-2H-Piran-2-yl)oxy]heptylaniline and Li2CuCl4in anhydrous tetrahydrofuran is stirred at minus 75°C for 1 h with the following molar ratio of the reactants [1-bromo-4(E)-hepten]:[7-[(tetrahydro-2H-Piran-2-yl)oxy]heptylaniline]:[Li2CuCl4]:[tetrahydrofuran]=1:1.2:0.03:20. Then the temperature of the reaction mixture slowly over 1 h to increase to 20°C and stirred at this temperature for another 10 hours a Further operation on the separation and purification of 11(E)-tetradecene-1-ol does not differ from the prototype. In the invention, the output 11(E)-tetradecene-1-ol increased to 82% (prototype - 67%). The overall yield of 11(E)-tetradeca-1-racette on the source acrolein is 41% (prototype - 33.5%), based on 1-bromo-4(E)-hepten - 77% (prototype - 63%). Contents Z)-isomer does not exceed 0.5%.

Example 1. Receipt 11 (E)-tetradecene-1-ol.

To 7-[(tetrahydro-2H-Piran-2-yl)oxy]heptylaniline obtained from 0.29 g of magnesium turnings and 3.35 g of 1-bromo-7-[(tetrahydro-2H-Piran-2-yl)oxy] heptane in 6 ml of dry tetrahydrofuran at -75°C. was dropwise added 1.77 g of 1-bromo-4(S)-Heptene in 7 ml of tetrahydrofuran. Then was added 3 ml of 0.1 M solution of Li2CuCl4in tetrahydrofuran and the mixture was stirred at -75°C for 1 h the Temperature of the reaction mixture slowly over 1 h was increased to 20°C and stirred for another 10 hours was Added 20 ml of a saturated solution of NH4Cl, stirred 1 h, the organic layer was separated and the aqueous was extracted with ether (3×30 ml). The combined organic solution was evaporated, the residue was dissolved in 20 ml of methanol containing 0.05 g of TsOH was stirred at room temperature for 24 h and was evaporated again. To the residue was added 50 ml of diethyl ether, then washed with saturated solutions of NaHCO3and NaCl, dried Mg2SO4and concentrated. The residue was chromatographically (SiO2, hexane-ether, 1:1). Yield 1.74 g (82%), nD201.4562. IR spectrum, ν, cm-1: 3335 (HE), 2961, 2926, 2853, 1458, 1057, 964 (TRANS-HC=). An NMR spectrum1N, δ, M. D.: 0.97 t (3H, CH3, J 7.3 Hz), 1.21-1.41 m (14N, CH2), 1.50-1.61 (m 2N,CH2CH2OH), 1.91-2.06 (m 4N,CH2CH=), 3.39 (1H, HE), 3.64 t (2H, CH2HE, J 6.6 Hz), 5.34-5.48 m (2H, CH=CH). Range of the Mr 13S, δ, ppm: 13.91 (14), At 25.52 (13), 25.70 (3), 29.11 (CH2), 29.39 (CH2), 29.45 (CH2), 29.50 (CH2), 29.55 (CH2), 29.59 (CH2), 32.50 (10), 32.71 (2), 62.83 (1), 129.31 (11), 131.80 (12).

Example 2. Receipt 11(E)-tetradeca-1-racette.

The mixture 0.367 g (1.73 mmol) 11(E)-tetradecene-1-ol, 1.23 g of anhydrous pyridine and 0.88 g of acetic anhydride was stirred at room temperature for 24 h, was added 20 ml of diethyl ether, then washed with saturated solutions of NaHCO3and NaCl, dried Mg2SO4and was evaporated. The residue was chromatographically (SiO2, hexane-ether 9:1). Output 0.414 g (94%), nD201.4481. IR spectrum, ν, cm-1: 2957, 2926, 2853, 1744 (C=O), 1366, 1238, 1040, 966 (TRANS-HC=). An NMR spectrum1N, δ, M. D.: 0.97 t (3H, CH3, J 7.4 Hz), 1.22-1.43 m (14N, CH2), 1.58-1.71 (m 2H, CH2CH2Oh), 1.94-2.18 m (7H, CH3C=O,CH2CH=), 4.06 t (2H, CH2Oh, J 6.6 Hz), 5.34-5.50 m (2H, CH=CH). An NMR spectrum13S, δ, ppm: 13.91 (14), 20.86 (CH3C=O), at 25.52 (13), 25.85 (3), 28.57 (2), 29.09 (CH2), 29.18 (CH2), 29.43 (SN2), 29.59 (CH2), 32.49 (10). 64.55 (1), 129.28 (11), 131.82 (12), 171.04 (C=O). Mass spectrum, m/z (IRel, %): 96 (34.41), 82 (72.55), 81 (at 37.93), 69 (29.43), 68 (77.45), 67 (52.06), 55 (at 62.13), 43 (100), 41 (58.77).

The proposed method has the following advantages:

1. Use up the available, cheap and safe catalyst with a small normal flow.

2. Higher output 11(E)-tetradeca-1-racette.

3. The absence of toxic waste.

The way to obtain 11(E)-tetradeca-1-racette, including the reaction of Grignard acrolein with ethylmagnesium obtaining 1-penten-3-ol, artevino the klaisen rearrangement involving 1-penten-3-ol and triethylorthoformate with obtaining the ethyl ester 4(E)-heptenophos acid, recovery of the ethyl ester 4(E)-heptenophos acid to obtain 4(E)-hepten-1-ol, substitution of the hydroxyl group of 4(E)-hepten-1-ol on VG to obtain 1-bromo-4(E)-Heptene, reaction cross-combination of 1-bromo-4(S)-Heptene with 7-[(tetrahydro-2H-Piran-2-yl)oxy]heptylaniline in the presence of the catalyst 11(E)-tetradecene-1-ol, acetylation 11(E)-tetradecene-1-ol with getting 11(E)-tetradeca-1-racette, characterized in that the cross-coupling of 1-bromo-4(S)-Heptene with 7-[(tetrahydro-2H-Piran-2-yl)oxy]heptylaniline with getting 11(E)-tetradecene-1-ol is carried out in the presence of a catalyst Li2CuCl4in the environment of tetrahydrofuran in the following molar ratio [1-bromo-4(E)-hepten]: [7-[(tetrahydro-2H-Piran-2-yl)oxy]heptylaniline]: [Li2CuCl4]: [tetrahydrofuran] = 1:1,2:0,03:20 for 1 h at a temperature of minus 75°C., then for 1 h at the temperature of minus 75°C to 20°C is for 10 h at 20°C.



 

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14 cl, 4 tbl, 20 ex

FIELD: chemistry.

SUBSTANCE: invention relates to an improved method, by which the carboxylic acid/diol mixture, that is suitable as the initial substance for the manufacture of polyester, obtained from the decolourised solution of carboxylic acid without actually isolating the solid dry carboxylic acid. More specifically, the invention relates to the method of manufacturing a mixture of carboxylic acid/diol, where the said method includes the addition of diol to the decolourised solution of carboxylic acid, which includes carboxylic acid and water, in the zone of the reactor etherification, where diol is located at a temperature sufficient for evaporating part of the water in order to become the basic suspending liquid with the formation of the specified carboxylic acid/diol mixture; where the said carboxylic acid and diol enter into a reaction in the zone of etherification with the formation of a flow of a complex hydroxyalkyl ether. The invention also relates to the following variants of the method: the method of manufacture of the carboxylic acid/diol mixture, where the said method includes the following stages: (a) mixing of the powder of damp carboxylic acid with water in the zone for mixing with the formation of the solution of damp carboxylic acid; where the said carboxylic acid is selected from the group, which includes terephthalic acid, isophthatic acid, naphthalenedicarboxylic acid and their mixtures; (b) discolourisation of aforesaid solution of damp carboxylic acid in the zone for reaction obtaining the decolourised solution of carboxylic acid; (c) not necessarily, instantaneous evaporation of the said decolourised solution of carboxylic acid in the zone of instantaneous evaporation for the removal of part of the water from the decolourised solution of carboxylic acid; and (d) addition of diol to the decolourised solution of carboxylic acid in the zone of the reactor of the etherification, where the said diol is located at a temperature, sufficient for the evaporation of part of the water in order to become the basic suspending liquid with the formation of the carboxylic acid/diol mixture; where the aforesaid carboxylic acid and diol then enter the zone of etherification with the formation of the flow of complex hydroxyalkyl ether; and relates to the method of manufacture of carboxylic acid/diol, where the said method includes the following stages: (a) the mixing of the powder of damp carboxylic acid with water in the zone for mixing with the formation of the solution of carboxylic acid; (b) discolourisation of the said solution of damp carboxylic acid in the reactor core with the formation of the decolourised solution of carboxylic acid; (c) crystallisation of the said decolourised solution of carboxylic acid in the zone of crystallisation with the formation of an aqueous suspension; and (d) removal of part of the contaminated water in the aforesaid aqueous solution and addition of diol into the zone of the removal of liquid with the obtaining of the said carboxylic acid/diol mixture, where diol is located at a temperature sufficient for evaporating part of the contaminated water from the said aqueous suspension in order to become the basic suspending liquid.

EFFECT: obtaining mixture of carboxylic acid/diol.

29 cl, 4 dwg

FIELD: chemistry.

SUBSTANCE: present invention pertains to improvement of the method of producing (met)acrylic acid and complex (met)acrylic esters, involving the following stages: (A) reacting propane, propylene or isobutylene and/or (met)acrolein with molecular oxygen or with a gas, containing molecular oxygen through gas-phase catalytic oxidation, obtaining crude (met)acrylic acid; (B) purification of the obtained crude (met)acrylic acid, obtaining a (met)acrylic acid product; and (C) reacting raw (met)acrylic acid with alcohol, obtaining complex (met)acrylic esters, in the event that the installation used in any of the stages (B) and (C), taking place concurrently, stops. The obtained excess crude (met)acrylic acid is temporarily stored in a tank. After restoring operation of the stopped installation, the crude (met)acrylic acid, stored in the tank, is fed into the installation, used in stage (B), and/or into the installation used in stage (C). (Met)acrylic acid output of the installation used in stage (A) should be less than total consumption of (met)acrylic acid by installations used in stages (B) and (C).

EFFECT: the method allows for processing (met)acrylic acid, temporarily stored in a tank, when stage (B) or (C) stops, without considerable change in workload in stage (A).

2 ex

FIELD: chemistry.

SUBSTANCE: invention relates to improved method of obtaining (meth)acrylic ester including stage of etherification of (meth)acrylic acid with C1-C4alcohol in presence of catalyst from highly acidic cation-exchange resin in form of immovable layer for obtaining (meth)acrylic ester; addition of polymerisation inhibitor into reactor or into distillation column for isolation; stage of isolation, at which (meth)acrylic acid that did not react is separated from reaction solution, obtained at reaction stage, where temperature in distillation column still is in the range from 60 to 100°C, and pressure at the top of distillation column is in the range from 1.33 to 26.7 kPa; and recirculation stage in order to return thus obtained (meth)acrylic acid, that did not react, to reaction stage, where solid substances, contained in isolated (meth)acrylic acid that did not react and is returned to reaction stage, are isolated from it. In industry used method of obtaining (meth)acrylic esters is improved in such way as to prolong service life of used in it catalyst from highly acidic cation-exchange resin.

EFFECT: elaboration of improved method of obtaining (meth)acrylic ester.

5 cl, 2 ex, 1 dwg

FIELD: chemistry.

SUBSTANCE: invention refers to advanced method of production of (meth)acrylic acid ester including (meth)acrylic acid purification by contacting raw (meth)acrylic acid containing manganese as an impurity manganese, and cation-exchange resin to remove manganese. To ensure contacting raw (meth)acrylic acid and cation-exchange resin, water is pre-added to (meth)acrylic acid. Besides, the method involves reaction of purified (meth)acrylic acid and alcohol with acid catalyst added.

EFFECT: method allows preventing effectively deactivation of the acid catalyst used in etherification reaction, equipment plugging and can ensure stable ester manufacturing.

3 cl, 5 tbl, 5 ex

FIELD: chemistry.

SUBSTANCE: invention concerns organic compound synthesis, particularly method of obtaining 4-biphenylmetacrylate of the formula . Obtained compound is applied in production of heat and weather resistant polymer materials. Claimed method involves dissolution of 4-phenylphenol in 10 wt % aqueous solution of caustic soda, further dosage of acylating agent in the form of metacrylic acid anhydride agent in reaction mix preliminarily cooled to 0-(+5°)C at such rate so as to keep the mix temperature below +10°C at molar ratio of 4-phenylphenol and metacrylic acid anhydride of 1:(1.1-1.5), reaction mix maturing at room temperature with stirring, organic layer extraction, flushing by alkali solution, and drying.

EFFECT: enhanced output of 4-biphenylmetacrylate, admixture content of non-reacted 4-phenylphenol reduced to 0,003-0,005 wt %.

3 cl, 1 tbl, 10 ex

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