SU1773901A1 - Method of obtaining benzyl propargilic esters - Google Patents

Description

The present invention relates to organic synthesis, in particular to a method for producing benzylpropargyl ethers that can be used in organic synthesis. In addition, benzylpropargyl ethers enhance the activity of insecticidal drugs and have juvenile hormonal activity.

Several methods are known for producing alkyl-, benzylpropargyl ethers. The authors of analog esters obtain propargyl esters from the corresponding allyl esters according to the following scheme:

H ₂ C = CHCH2OH + Alk-X H ₂ C = = CHCH ₂ OA1k, where X = Br, 0S02Alk,

H2C = CHCH ₂ OA1k + Br2 BrCH2CHBVgCH ₂ OA1k.

BrCH ₂ CHBrCH ₂ OAIk Н ₂ С = = CBgCH2ОА1к,

H ₂ C = CBgCH ₂ OA1k HC = = CCH ₂ OA1k.

The authors do not indicate the yield and reaction conditions.

The main disadvantages of this method are the multistage nature and the use of expensive and scarce bromine.

In the work (prototype / authors obtained benzyl propargyl ether from benzyl chloride and propargyl alcohol, under the action of a 50% aqueous solution of sodium hydroxide in the presence of a catalyst triethylbenzylammonium chloride (TEBAH), at a temperature of 36 ° C.

1773901 A1

The reaction was carried out according to the following scheme:

НСнССН ₂ ОН + С1СН ₂ - ©> ^HCscc '-i ₂ OCH ₂ - ©>

The benzyl propargyl ether yield was 72%,

The main disadvantages of the method:

1. Low yield of the target product.

2. Use of expensive and scarce propargyl alcohol.

The aim of the invention is to increase the yield of the target product of the formula

R, -Q-ch ₂ och ₂ c = ch, k _r R _s (I) 'where Ri = R2 = R3 ⁼ H;

R1 = CI, Rz = R3 = H;

Ri = R2 = CI, Pz = H;

R1 = R ₃ = CI, R2 = H.

This goal is achieved by the interaction of the corresponding benzyl chloride, cis-3-chloropropenol-1 and 45-50% aqueous sodium hydroxide solution, in the presence of catalysts: quaternary ammonium salts (QAS) of the general formula RiR2R3R4N ⁺ X ', where Ri. R2 - C1-C4-alkyl, R3 - Ci-Cis-adkyl, R4 - CgCd-alkyl, allyl, benzyl, with a total carbon atom content of at least 8, X-Cl, B g, taken in an amount of 1-3 wt% of the organic part of the reaction mass, and the process is carried out at a molar ratio of benzyl chloride: cis-3chloropropenol-1 combined solution of sodium hydroxide, equal to 1: 1.10-1.20: 5.0-6.0 at a temperature of 60-80 ° C.

The essence of the method is as follows. Benzyl chloride, cis-3-chloropropenol-1, QAC and 45-50% aqueous NaOH solution are loaded into a reactor equipped with a stirrer, a thermometer and a reflux condenser. With vigorous stirring, the reaction mixture is kept at a temperature of 60-80 ° C for 2-6 hours. The product is isolated by known methods. Exit. 90.0-99.5%.

The method is illustrated by the following examples.

Example 1. In a flask with a volume of 500 ml, equipped with a stirrer, thermometer and reflux condenser, load 51.9 g of cis-3-chloropropenol-1.62.0 g of benzyl chloride and 2.3 g of tetrabutylammonium bromide. With stirring, load 240 g of a 50% aqueous NaOH solution. The mixture was heated to 70 ° С and kept under vigorous stirring for 3 h. Then the heating was removed, 100 ml of water was charged into the reactor and cooled to room temperature. The organic phase is separated. The aqueous layer was extracted with ether, the ether extract was combined with the organic phase, washed with an acidified NaCl solution, then with water until neutral, dried under Na2SO4. The ether is removed, the product is distilled under vacuum. 70.8 g of benzylpropargyl ether are obtained. The yield is 98.9%.

Example 2. Experimental conditions are identical to example 1. Load 51.9 g of cis-3-chloropropenol-1, 62.0 g of benzyl chloride, 4.3 g (53 wt.%) Of an aqueous solution of catamine AB (2.3 g). The reaction time is 6 hours. 68.9 g of benzyl propargyl ether are obtained. The yield is 96.2%.

Example 3. Synthesis conditions are similar to example 1. Catalyst tetraethylammonium bromide - 2.3 g. Reaction time 6 h. Received 69.3 g of benzyl proopargyl ether. The yield is 96.8%.

Example 4. Under the conditions of example 1. Catalyst TEBAH - 3.4 g. Reaction time 6 hours Obtained 68.1 g of benzylpropargyl ether. The yield is 95.1%.

Example 5. Under the conditions of example 1. Catalyst triethylallylammonium bromide - 2.8 g. Reaction time 6 hours Obtained 68.7 g of the target product. The yield is 95.9%.

Example 6 (4-Chlorobenzylpropargyl ether).

The conditions for the synthesis are the same as in example 1. Download 51.9 g of cis-Zchloropropenol-1, 78.6 g of 4-chlorobenzyl chloride, 2.7 g of tetrabutylammonium bromide and 240 g of 50% NaOH. The reaction time is 4 hours. 86.7 g of product are obtained. The yield is 98.3%.

PRI me R 7. (2,4-Dichlorobenzylpropargyl ether).

The conditions are the same as in example 1. Download 51.9 g of cis-3-chloropropenol-1, 95.4 g of 2,4-dichlorobenzyl chloride, 3.0 g of tetrabutyl allylammonium bromide and 240 g of 50% NaOH. The reaction time is 4 hours. 102.1 g of product are obtained. The yield is 97.3%.

Example 8 (3,4-Dichlorobenzylpropargyl ether).

The conditions are identical. Download 51.9 g of cis-3-chloropropenol-1, 95.4 g of 3,4-dichlorobenzyl chloride, 3.0 g of tetrabutylammonium bromide and 240 g of 50% NaOH. The reaction time is 4 hours. 101.9 g of product are obtained. Yield 97.1%.

The dependence of the yield of benzylpropargyl ether on the reaction conditions and the molar ratio of the reagents are shown in the table.

The use of QACs containing less than 8 carbon atoms at the nitrogen atom as catalysts leads to a significant decrease in the yield of the target product. Other QAC exhibit the same catalytic activity as the catalysts indicated in the above examples.

Thus, the proposed invention has the following advantages: high yield of the target product; use of industrial waste - 1,3-dichloropropene to obtain valuable organic compounds;

exclusion of scarce propargyl alcohol from the process of obtaining benzylpropargyl ethers.

Claims (1)

Claim of invention A method for producing benzylpropargyl ethers of the general formula R _t - ^ - CH ₂ OCH ₂ C = CH, r ₂ r ₃ where Ri = R2 = R3 - Η; Ri is Cl, R2 = R3-H; R1 = R ₂ -CI. R3-H; Ri = R3-Cl, R2-H; the interaction of the corresponding benzyl chloride with an unsaturated alcohol in the presence of a 45-50% aqueous solution of sodium hydroxide and a catalyst - a quaternary ammonium salt at an elevated temperature, characterized by the fact. 10 that, in order to increase the yield of the target product, cis-3-chloropropeno is used as an unsaturated alcohol.n-1, and a quaternary ammonium salt of the general formula is used as a catalyst 15 R1R2R3R4NX. where Ri, R2 is CgCd-alkyl; R3 is Ci-Cia alkyl; R4 - CgC ^ -alkyl, allyl, benzyl, with a total carbon atom content of at least 20 8, where X is Ci, BrO taken in an amount of 1-3 wt% of the organic part of the reaction mass, and the process is carried out at a molar ratio of benzyl chloride: cis-3-chloropropenol-1: aqueous solution of sodium hydroxide, equal to 1: 1.10 1.20: 5.0-6.0, at 60-80 ° C. Catalyst - tetrabutylammonium bromide No. · experiences The molar ratio of cis-3-chloropropenol1: benzyl chloride NaOH: benzyl chloride molar ratio May NAOH concentration. % ^; Catalyst, May. % Temperature, ° C | Time, h Exit, % ¹ 1.15 6.0 50.0 2.0 70 3.0 98.7 2 1.15 6.0 45.0 2.0 70 4.0 97.7 ³ 1.15 6.0 40.0 2.0 70 7.0 89.4 4 1.00 6.0 50.0 2.0 70 7.0 88.7 five 1.10 6.0 50.0 2.0 70 3.0 96.5 6 1.20 6.0 50.0 2.0 70 3.0 99.6 7 1.25 6.0 50.0 2.0 70 3.0 99.5 ' ⁸ 1.15 6.0 50.0 1.0 70 5.0 96.2 ^nine 1.15 6.0 50.0 0.5 70 8.0 87.9 ten 1.15 6.0 50.0 3.0 70 2.0 98.9 eleven 1.15 6.0 50.0 3.5 70 2.0 98.7 12 1.15 5.0 50.0 2.0 70 - 4.0 97.8 13 1.15 4.0 50.0 2.0 70 8.0 88.8 fourteen 1.15 6.0 50.0 2.0 60 5.0 95.7 fifteen 1.15 6.0 50.0 2.0 50 7.0 87.2 sixteen 1.15 6.0 50.0 2.0 80 2.0 98.8 1.15 6.0 50.0 2.0 85 2.0 98.7