CN86102956A - The auxiliary pyrocatechol etherification of water - Google Patents

Abstract

A kind of method has shown promotion pyrocatechol and the effect of methylallyl chloride selective etherification in the presence of no catalyst for etherification, wherein with a kind of solvent systems of being made up of an aliphatic ketone and the auxiliary water gaging of an etherification.

Description

The auxiliary pyrocatechol etherification of water

The present invention relates to a kind of manufacture method of a kind of intermediate 2-methylallyl oxygen base phenol in the commercial sterilant carbofuran of preparation.More particularly, the present invention relates to a kind of pyrocatechol and methylallyl chloride from the mixed solvent system of forming by control water gaging and aliphatic ketone at and make the method for 2-methylallyl oxygen base phenol, thereby eliminated needs the etherification catalyzer.

It is that the technician is known in this field that pyrocatechol and methylallyl chloride reaction produce 2-methylallyl oxygen base phenol, and because for desirable product, it is inconvenient will obtaining fast speed of reaction, high selectivity and the abundant conversion that obtains pyrocatechol simultaneously, so above-mentioned reaction has become important research project problem.

People in this field know, can carry out etherificate to pyrocatechol and other dihydroxyl phenol in various organic solvents.United States Patent (USP) the 2nd, 362 has been narrated for No. 479 to return in alcoholic potash and has been heated up in a steamer Resorcinol and methylallyl chloride.United States Patent (USP) the 3rd, 274 has been narrated for No. 260 and have been used big water gaging and immiscible organic solvent such as benzene, alkyl benzene or halogenated hydrocarbon, makes the alkylation of dihydroxyl phenols with a kind of alkylogen, alkyl sulfuric ester or tosylate.

United States Patent (USP) the 3rd, 474, No. 171 and hungarian patent have been narrated the reaction of pyrocatechol and methylallyl chloride in aliphatic ketone such as acetone or methyl ethyl ketone for the 173rd, No. 437.United States Patent (USP) the 3rd, 927,118 and 4 50, narrated the application that organic dipolar nature aprotonic solvent comprises amides, sulfone class, sulfoxide class, ethers and arene No. 333.United States Patent (USP) the 4th, 321,204 and 4,390, narrated the application of the 1 monoalkyl ethers that contains at least one free OH group and various other alcohols and polyalcohols No. 733.

Known that the reaction between pyrocatechol and the methylallyl chloride can carry out in the presence of a kind of organic solvent and water, but only urged in the presence of agent such as potassiumiodide or a kind of phase-transfer catalyst in a kind of etherificate of costliness.A kind of like this catalyst for etherification not, this reaction just is difficult to carry out, and carries out quite slowly, if or pressure carry out, then produce excessive undesirable by product.For example, in No. the 4th, 252,985, No. the 92102nd, European patent and United States Patent (USP), this reaction is with the derivatives catalysis of quaternary ammonium Huo Phosphonium; At United States Patent (USP) the 4th, 465, in No. 868, it uses various catalysis of iodine.

The invention provides a kind of economy and method high yield for preparing 2-methylallyl oxygen base phenol from pyrocatechol and methylallyl chloride.This inventive method is used a kind of water/ketone solvent system, and this system has several advantages that technology is arranged earlier that obviously surpass, comprising catalyst for etherification and the later needs that reclaim catalyzer eliminated costliness.Speed of reaction equals or faster than with the resulting speed of reaction of method is arranged earlier, and the selectivity of 2-methylallyl oxygen base phenol is about 90% or higher.

According to the present invention, a kind of method of the 2-of preparation methylallyl oxygen base phenol is provided, wherein pyrocatechol and methylallyl chloride are reflected in 70 ℃ to the 150 ℃ temperature ranges, from by the alkaline carbonate class, the alkaline metal bicarbonate class, under existing, a kind of alkali of selecting for use in one group of alkali that alkaline earth carbonate class and alkaline earth heavy carbonic salt are formed carries out, wherein said reaction is under the situation of no iodide and phase transition catalyst for etherification, in the presence of the solvent systems of forming by water and a kind of aliphatic ketone, carry out with 4 to 8 carbon atoms, described solvent systems is that every mole of pyrocatechol contains 0.35 to 1.85 mole of water, and used solvent sum will make the concentration of pyrocatechol be within 5% to 50% the scope of weight of solvent.

In the method for the invention, the conversion limitations of pyrocatechol is about 40% to 70%, preferably 45% to about 55%, improving the maximum selectivity of 2-methylallyl oxygen base phenol and to reduce undesirable by product, as pyrocatechol diether and/or the product that has a cycloalkyl No. 4 positions.The undesirable by product of these of this reaction can not be cyclized into 2,3-dihydro-2,2-dimethyl-7-hydroxyl benzofuran, this be a kind of can be by carbamoylation to form the intermediate of carbofuran.In this resulting product, exist a small amount of 3-methylallyl pyrocatechol, and it can easily be converted into 7-hydroxyl benzofuran intermediate and 2-methylallyl oxygen base phenol.

By the known certain methods of technician in this field, can the conversion of pyrocatechol be provided in the above-mentioned scope that provides, these methods have by utilizing every mole of pyrocatechol to contain 0.4 to about 0.75 mole of methylallyl chloride or alkali, or during by the monitoring reaction pyrocatechol consumption and when desirable consumption has reached stopped reaction.

This reaction is at 70 ℃ to 150 ℃, and preferably 110 ℃ are carried out to the temperature of 140 ℃ of scopes.When this temperature of reaction was not critical temperature, selected temperature of reaction reached influence the needed reaction times of transforming degree of desirable pyrocatechol.Equally clearly, if the boiling point of used solvent systems is lower than the boiling point of selected temperature of reaction, necessity makes to be reflected under the certain pressure and carries out to reach temperature desired so.

The used bases of the present invention is more suitable the alkaline carbonate class, and optimal is yellow soda ash or salt of wormwood, or their mixture.When using yellow soda ash or salt of wormwood, it would be desirable the yellow soda ash that adopts too much mole number, therefore, the molar ratio of yellow soda ash and salt of wormwood is more suitable be in about 5: 1 or about 20: 1 scope in.

The amount of used solvent can be very different in this reaction, it would be desirable in general the concentration that makes pyrocatechol with enough solvents for based on the weight of the initial amount of pyrocatechol and solvent 5% to about 50%, be preferably 15% to 35%.

The amount of water must be limited in the narrow scope in this solvent systems, to reach the highly selective to 2-methylallyl oxygen base phenol, reaches very favourable speed of reaction simultaneously.Contain 0.3 mole of water of having an appointment if the water yield in this solution system is lower than every mole of pyrocatechol, speed of reaction just becomes and can not accept ground slowly so.Contain when having an appointment more than 1.9 moles water when using every mole of pyrocatechol in this solvent systems, selectivity to 2-methylallyl oxygen base phenol will significantly descend, thereby produce a kind of undesirable by product that can not receiving amount, according to realizing best model of the present invention, it would be desirable that using every mole of pyrocatechol contains 1.1 to a kind of solvent systems of about 1.5 mole of water and the conversion that reaches 45% to 55% pyrocatechol.

The ketone that is applicable to this solvent systems is aliphatics (as the alkyl) ketone that contains 4 to 8 carbon atoms, comprises methyl ethyl ketone, metacetone, methyl iso-butyl ketone (MIBK) etc.Following embodiment illustrates enforcement of the present invention with methyl iso-butyl ketone (MIBK) as the organic component of this solvent systems.

Embodiment 1A-1E

In a stirred autoclave that hygrosensor and liquid sampling pipe is housed, each reaction adds following article: 66.0 gram pyrocatechols (0.6 mole), 34.2 gram methylallyl chlorides (0.36 mole), 35.0 gram anhydrous sodium carbonates (0.33 mole), 4.14 gram Anhydrous potassium carbonates (0.03 mole), 0.55 gram V-Brite B (0.003 mole) and 200 restrain the solvent that contains methyl iso-butyl ketone (MIBK) (MIBK) and different water gagings.This system purifies with nitrogen, begins to stir, and internal temperature rises to 130 ℃.Small amount of sample is extracted in each reaction termly, and follow the tracks of the progress of etherification with gc analysis.When the conversion of about 50% pyrocatechol had reached, internal temperature was reduced to 20 ℃ after 10 minutes.

Every kind of rough reaction product is transferred to one and is equipped with in 1 liter of three neck round-bottomed flask that a bottom accesses valve, a pneumatic tetrafluoroethylene blade agitators and a nitrogen purging device.Begin to stir raw material, and add the distilled water of the 150 gram degassings.In 15 minutes, 50 gram concentrated hydrochloric acids (0.50 mole) are added the alkali that exists with neutralization at leisure.The adding speed of hydrochloric acid is such degree, and is controllable by the caused foam of emitting of carbonic acid gas.After hydrochloric acid adds, continue to stir 15 minutes.Allow be separated 15 minutes, the salt solution (PH=2) that is produced is reclaimed, weighs and analyzes 2-methylallyl oxygen base phenol and pyrocatechol with high pressure lipuid chromatography (HPLC).Organic phase is reclaimed, weighed and with gc analysis 2-methylallyl oxygen base phenol, pyrocatechol and by product.For each water yield, calculate the conversion of pyrocatechol and to the selectivity of 2-methylallyl oxygen base phenol; These results list in 1E as embodiment 1A in table 1.Reaction times is along with water-content contains that 0.37 mole of water is increased to that every mole of pyrocatechol contains 1.85 mole of water and shortens (embodiment 1A to 1D) greatly from every mole of pyrocatechol, and not remarkably influenced is to the reaction preference of 2-methylallyl oxygen base phenol.When water/pyrocatechol ratio increases to 3.7(embodiment 1E from 1.85) time, what be accompanied by the reaction times shortening is that selectivity is low relatively poor.

Embodiment 2A-2H

These embodiment utilizations method identical with embodiment 1A-1E, and except the following points, (1) used alkali is yellow soda ash, rather than the mixture of yellow soda ash and salt of wormwood, (2) in embodiment 2D and 2E, adopt 37.1 gram (0.39 mole) methylallyl chlorides and in embodiment 2F to 2H, restrain (0.42 mole) methylallyl chlorides with 39.9.These routine results show that once more the reaction times can continue to correct along with the increase of water-content, but when high water of employing and pyrocatechol ratio, but lost selectivity.

Table 1

Water/pyrocatechol ratio reaction times pyrocatechol transforms selectivity

Embodiment (mole) (minute) (per-cent) (per-cent)

1A 0.37 175（175） 45.8 95.6

1B 1.11 145（140） 46.1 95.1

1C 1.48 145（110） 47.2 93.8

1D 1.85 145（110） 50.4 92.4

1E 3.70 115（80） 46.8 90.4

2A 0 170（150） 45.0 92.0

2B 1.48 175（135） 48.5 92.3

2C 1.85 145（120） 48.8 88.6

2D 1.48 115（115） 45.6 93.6

2E 1.85 115（115） 46.6 94.3

2F 1.85 115（115） 50.9 89.2

2G 2.78 85（85） 50.3 88.2

2H 3.70 85（75） 50.4 86.5

1. not having the time of parantheses is the real reaction time, comprises 25-30 minute temperature rise period.These times usually surpass the required time of production peak that obtains.Best Times is illustrated in the parantheses, and is from the reaction times the percentile curve calculation of area based on the 2-methylallyl oxygen base phenol of reaction mixture gas chromatographic analysis to be obtained.

Claims (7)

1, a kind of being included in 70 ℃ to 150 ℃ the temperature range, be selected from the presence of the alkali of alkaline carbonate class, alkaline metal bicarbonate class, alkaline earth carbonate class and alkaline earth heavy carbonic salt group at one or more, the method of pyrocatechol and methylallyl chloride prepared in reaction 2-methylallyl oxygen base phenol, described reaction is not have in the presence of the catalyst for etherification, in the solvent systems of forming by water and a kind of aliphatic ketone, carry out, it is characterized in that every mole of pyrocatechol is with 0.35 to 1.85 mole of water with 4 to 8 carbon atoms.

2, the described method of claim 1 is characterized in that in the described method, and every mole of pyrocatechol is with the methylallyl chloride of 0.4 to 0.75 mole of equivalent.

3, the described method of claim 2 is characterized in that in the described method, the conversion of pyrocatechol in 45% to 55% scope and solvent systems contain every mole of pyrocatechol 1.1 to 1.5 mole of water arranged.

4, the described method of claim 3 is characterized in that in the described method that the ketone that is used for solvent systems is methyl iso-butyl ketone (MIBK).

5, the described method of claim 2 is characterized in that in the described method, and alkali is a kind of alkaline carbonate that is selected from yellow soda ash, yellow soda ash and potassium carbonate mixtures.

6, the described method of claim 5 is characterized in that in the described method that alkali is yellow soda ash.

7, the described method of claim 5 is characterized in that in the described method that the molar ratio scope of used yellow soda ash and salt of wormwood is 5: 1 to 20: 1.