RU1810349C - Method of synthesis of 3-alkoxycarbonyl - 2 - methyl - 2 - propenylphosphonic acid diisopropyl esters - Google Patents

Abstract

SUMMARY OF THE INVENTION: the product is 3-isopropoxycarbonyl-2-methyl-2-propenylphosphonic acid diisopropyl ester of f-ly (iso-СЗН 0) 2Р (0) СН2-С (СНз) - СН-СООСН (СНз) СНз , BP C HarOsP, 90% yield, 3-ethoxycarbonyl-2-methyl di-isopropyl ester of l-2-propene and lphosphonic acid of ph-ly (iso-СЗН 0) 2Р (0) СН2-С (СНз СН -COOCHANCH3 BF Ci3H250sP, yield 92%. Reagent 1: CH3-C (CH3) - CH-CO-OCH (H) CH3, where RH, CH3. Reagent 2: bromosuccinimide. Reagent 3: () sp. Reaction conditions: in the presence of benzoyl peroxide with a molar ratio of reagents 1 and 2 equal to (4.5-6.0): 1. I interact with the reagents 1 and 2 t at 80-90 ° C, treatment of the resulting reaction mixture with reagent 3 is carried out at 130-160 ° C. 1 table.

Description

The invention relates to organic chemistry, in particular to an improved method for the preparation of 3-alkoxycarbonyl-2-methyl-2-propenylphosphonic acid diisopropyl esters of the general formula I

I'm mr

(1-C3H70) g-P-CHg-C CH-COOSCH.

where R N or CH,

which are widely used for the synthesis of unsaturated esters with valuable physiological active properties (hormonal insecticides) or which are intermediate products for the production of vitamins and others. The aim of the invention is to increase the yield and simplify the process.

The goal is achieved by the proposed method for the preparation of diisopropyl esters of 3-alkoxycarbonyl-2-methyl-2-propenylLphosphonic acid (phosphonates) of the general formula I:

m7Hz R (1-s3n7o) 2-P-sngs sn-co-ssns-1,

where R N or CH,

which consists in the fact that the ester of 3-methyl-2-butenoic acid of General formula II

CH3 t e I

СН5-С СН-СООСНСН3,

where R has the indicated meanings.

00

about

C) Јь

Yu

subjected to bromination with bromosuccinimide in the presence of benzoyl peroxide at a temperature of 80-90 ° C with a ratio of ibromsuccinimide ester equal to (4.5-6): 1 and the resulting 4-bromo-3-methylbutanoic acid ester (III) after separation of the succinic nimide is reacted with triisopropyl phosphite at a temperature of 140-160 ° C with simultaneous distillation of isopropyl bromide and subsequent distillation of 3-methyl-2-butenoic acid (II) ester in vacuum. The result is a slightly colored phosphonate of 90% purity, which does not require further purification for use in the synthesis. The product yield is 90% in two stages, i.e. counting on bromosuccinimide.

Excess distilled 3-methyl-2-butenoic acid ester (II) after washing with sodium bicarbonate solution and water, drying and distillation can be returned to the process. ,:

Distinctive features of the proposed method are the bromination of methylbutenic acid ester 3 with bromosuccinimide at a ratio of ibromsuccinimide ester equal to (4.5-6): 1i and the production of phosphonates in the same medium without isolation of the 4-bromo-3 ester formed in the first stage -methylbutenic acid, followed by distillation of the starting ester, washing with sodium bicarbonate solution and water, drying and returning to the process.

Example 1. Preparation of diisopropyl ether of Z-iZopropoxycarbonyl-2-methyl-2-propenylphosphonic acid (16).

2.18 kg (2.5 l) (calculated as 100%; 15.36 mol) of methylbutenic acid isopropyl ether, 3.5 g of benzoyl peroxide and 110 g of dried filter paper are charged into a 3-liter reactor equipped with a stirrer and a thermometer. g bromine uccinimide. The suspension is heated with stirring to 80 ° C, by raising the temperature by 2-3 ° C, the onset of the reaction is detected, another 110 g of bromosuccinimide are added, after 20 minutes - another 110 g, and after 20 minutes the last batch is 110 g. 440 g of bromosuccinimide (2.47 mol). The ratio of ether to bromosuccinimide 6: 1. After 25 minutes of heating at 80-85 ° C, after the last portion was added, the suspension was cooled to 20-25 ° C. The cooled suspension is filtered on a suction filter to separate succinimide. The precipitate was washed on a filter with 300 ml of hexane. Wash hexane is collected separately from the main filtrate.

510 g (in terms of 100%, 2.45 mol) of triisopropylfrsfit and half of the filtrate resulting from the bromination of isopropyl ether are placed in a 3-liter reactor equipped with a stirrer with a shutter, a thermometer, a dropping funnel and a direct refrigerator with a receiver. methylbutenic acid. The second half of the filtrate is transferred to a dropping funnel. The solution in the reactor is gradually heated with stirring to

0 130 ° C in the mass. At this temperature, a phosphonate formation reaction begins, the result of which is the start of distillation of ispropyl bromide. As isopropyl bromide is distilled off gradually over 1.5-2. h pr

5 130 ° C add the second half of the filtrate from the bromination reaction from the dropping funnel. Upon completion of the addition, the mass temperature was raised to 160 ° C and held at that temperature for 1.5 hours (the distillation of isopropyl bromide practically stopped), after which a sample was taken to control the end of the reaction (GLC). If brominated ether is present in the mixture, heating is continued for another 30 minutes and again

5 take a sample. If brominated ether is still present, a certain amount of triisopropylphosphite is added and heating is continued for another 20 minutes. If the reaction is complete, the contents of the reactor are cooled to 35-40 ° C.

The reactor is sealed, the receiving flask is replaced, the capillary is introduced into the mass, and a residual pressure of 25-30 mm Hg is created in the system. and gradually heat the contents. Residues of isopropyl bromide are distilled off from the reactor, and then at isopropyl ether of methylbutenic acid, diisopropylphosphite and other impurities in vapor at 70-80 ° C. After distillation of the main amount of volatile substances, the residue is transferred to a 1 liter cube, where a residual pressure of 0.5-1.0 mm Hg is created. and at a bath temperature of 140 ° C, the stripping of the volatiles is completed and the mass is cooled. The residue is the intermediate intermediate of juvemon production, the phosphonate component. Weight 600-630 g, the content of the hereditary substance 92% (GLC). The yield (100% phosphonate) calculated on the basis of 90% bromosuccinimide, Phospho nate, without additional treatment, is directed to the production of juvemon.

Example 2 Preparation of 3-e hydroxycarbonyl-2-methyl-2-propenylphosphonic acid diisopropyl ester (la).

5 By a method analogous to example 1, based on 695 g (in terms of 100%; 5 microns) of methylbutenoic acid ethyl ester and 178 g (1 mol) of bromosuccinimide at a bromination temperature of 85-90 ° C, 298.8 g of diisopropyl ether were obtained

3-ethoxycarbonyl-2-methyl-2-propenylphosphonic acid, 90% basic substance content (GLC), Yield (100% phosphonate) based on 92% bromosuccinimide. Phosphonate without further processing is directed to obtain hydroprene,

The table shows data on varying reaction conditions (Examples 3-8).

The advantages of the proposed method are to increase the yield of the product and simplify the process. Thus, in general, the proposed method can significantly increase the yield of the target product (from 60 to 90%) and simplify the process.

Formula and zobren N and Method for the preparation of diisopropyl esters of 3-alkoxycarbonyl-2-methyl-2-propenylphosphonic acids of the general form

ly ./ ... -. ,., - /. . .---. ; .l. - ;. ..-. .; I 9nz: - ..

, (i-C3H70) 2-P-CH2-C CH-COOCHCH,

where R is hydrogen or methyl,

reservation of ether 3-methyl-2-butene

acids of the general formula

0

5

0

CH:

I

R

СН3-С СН-СООСНСН3,

where R has the indicated meanings, with bromosuccinimide in the presence of benzoyl peroxide at 80-90 ° C followed by treatment of the resulting 4-bromo-3-methyl-2-butenoic acid ester with triisopropylphosphite at 130-1 ° C with simultaneous distillation of isopropyl bromide, This is due to the fact that, in order to simplify the process and increase the yield of the target products, bromination is carried out at a molar ratio of 3-methyl-2-butenoic acid ester to bromosuccinimide (4.5-6.0): 1 and the resulting reaction mixture after separation of the succinimide is fed to the treatment of triisopropyl osfitom, followed by distilling off the ether in vacuo W-methyl-2-butenoic acid.

Preparation of 3-alkoxycarbon1 / 1l-2-methyl-2-propenylphosphonic diisopropyl esters

acids of the general formula I

I AM

(i-C3H70) 2-P-CH2-C CH-COOCHCH3 R H; 1br SNZ

I AM

Oh

P-CH2-C CH-COOCHCH3; 1br SNZ