CN101811941A

CN101811941A - Preparation method for o-hydroxy-phenyl alkyl ether

Info

Publication number: CN101811941A
Application number: CN201010123113A
Authority: CN
Inventors: 马学兵; 洪炜; 肖琳珊; 赵华文; 韦勇; 谭修万
Original assignee: CHONGQING THRIVE CHEMICAK Co Ltd
Current assignee: CHONGQING THRIVE CHEMICAK Co Ltd
Priority date: 2010-03-12
Filing date: 2010-03-12
Publication date: 2010-08-25

Abstract

The invention discloses a method for preparing o-hydroxy-phenyl alkyl ether shown as a formula I which is obtain by adopting pyrocatechol and halohydrocarbon shown as the formula I as starting materials to carry out Williamson reaction in the presence of alkali, wherein the adopted alkali is the mixture of sodium hydroxide, sodium carbonate and potassium carbonate or the mixture of sodium hydroxide and potassium carbonate, and the reaction is carried out under the protection of inert gas. By adopting the method of the invention, by-product generation can be reduced, product yield can be greatly improved, production cost is lowered and environmental pollution is decreased simultaneously.

Description

The preparation method of o-hydroxy-phenyl alkyl ether

Technical field

The present invention relates to the preparation method of compound, particularly the preparation method of o-hydroxy-phenyl alkyl ether.

Background technology

Ortho-hydroxyanisole and 2-ethoxy-phenol are important fine chemical material, are widely used in the synthetic of medical chemistry product, spices and dyestuff, in particular for synthesizing of spices vanillin food grade,1000.000000ine mesh.

The ortho-hydroxyanisole of bibliographical information and the preparation method of 2-ethoxy-phenol are by different two classes that mainly are divided into of starting raw material: (1) is starting raw material with corresponding Ortho Anisidine or o-phenetidine, makes through diazotization, hydrolysis reaction; (2) with the pyrocatechol be starting raw material,, perhaps, make through alkylation reaction with corresponding halohydrocarbon with corresponding methyl-sulfate or ethyl sulfate.

The Williamson reaction takes place with corresponding halohydrocarbon and makes ortho-hydroxyanisole or 2-ethoxy-phenol in pyrocatechol in the presence of alkali:

Though this method is widely used, but still there are two problems in suitability for industrialized production:

(1) pyrocatechol and halohydrocarbons reaction easily generate the pyrocatechol dialkyl ether:

(2) pyrocatechol easily is oxidized to quinones substance under alkalescence, hot conditions:

Because the generation of above-mentioned two by products causes the yield of ortho-hydroxyanisole or 2-ethoxy-phenol lower, production cost is higher, and environmental pollution is bigger.

Summary of the invention

In view of this, the object of the present invention is to provide a kind of preparation method of o-hydroxy-phenyl alkyl ether, can reduce the generation of by product, improve target product yield, reduce production costs, reduce environmental pollution.

For achieving the above object, the present invention adopts following technical scheme:

The preparation method of o-hydroxy-phenyl alkyl ether shown in the general formula I is to be starting raw material with halohydrocarbon shown in pyrocatechol and the general formula I I, the Williamson reaction takes place in the presence of alkali and makes:

In general formula I and general formula I I, R is methyl or ethyl, and X is a chlorine or bromine; Described alkali is the mixture of sodium hydroxide, yellow soda ash and salt of wormwood or is the mixture of sodium hydroxide and salt of wormwood that described being reflected under the protection of inert gas carried out.

Further, described alkali is the mixture of sodium hydroxide and salt of wormwood;

Further, described rare gas element is nitrogen or argon gas.

Beneficial effect of the present invention is: the Williamson of pyrocatechol and halohydrocarbon reacts the mixture that employed alkali is sodium hydroxide and yellow soda ash in (1) prior art, the present invention partly substitutes or replacing whole yellow soda ash with salt of wormwood, generate the sylvite of pyrocatechol monoalky lether when reaction after, because the volume of potassium ion is big than sodium ion, to introduce second alkyl exist sterically hindered, thereby reduced the generation of pyrocatechol dialkyl ether; (2) the present invention carries out being reflected under the protection of inert gas of pyrocatechol and halohydrocarbon, prevents the oxidation of pyrocatechol under alkaline hot conditions, thereby has reduced the generation of quinones substance; Adopt above-mentioned two kinds of measures to reduce the generation of by product, the yield of ortho-hydroxyanisole of the present invention or 2-ethoxy-phenol reaches 85～95.6%, increases by 6.0～7.4% than existing methods, and simultaneously, production cost reduces, and environmental pollution reduces.

Embodiment

In order to make the purpose, technical solutions and advantages of the present invention clearer, below the preferred embodiments of the present invention are described in detail.

One, raw material and equipment

Pyrocatechol (purity 〉=98.5%) is available from Lianyungang Sanjili Chemical Industrial Co., Ltd; Methyl chloride (purity 〉=99.5%) and monochloroethane (purity 〉=99.5%) are available from Zi Gong, Sichuan letter crane chemical industry company limited; GAH-5 type autoclave converges prosperous chemical machinery company limited available from Weihai, Shandong.

Two, the preparation of ortho-hydroxyanisole

In autoclave, add pyrocatechol 47.1g, toluene 150g and polyoxyethylene glycol 8002.4g, tighten autoclave, vacuumize, in still, charge into rare gas element, (400r/min) slowly adds aqueous solution 50mL, yellow soda ash and/or the wet chemical 80mL that is dissolved with sodium hydroxide 16.1g by discharge port in still under agitation condition again, finish and continue to stir 5 minutes, tighten autoclave, in still, slowly charge into methyl chloride 30.3g, open and stir, be warming up to 140 ℃, reacted 5 hours, be cooled to room temperature, discharging; Reaction solution is transferred in the separating funnel standing demix, collected organic layer and water layer respectively, the organic layer massfraction is that 10% aqueous sodium hydroxide washes is washed (the 1st 150mL 3 times, 2nd, 3 each 50mL), vacuum distillation recovered solvent promptly gets pyrocatechol dme (being bis ether); Alkaline wash and water layer merge, and being neutralized to pH with concentrated hydrochloric acid is 2～3, with 3 times (the 1st 150mL, the 2nd, 3 each 50mL) of toluene extraction, and the combining methylbenzene extraction liquid, vacuum distillation recovered solvent promptly gets ortho-hydroxyanisole (being monoether).

Concrete preparation condition and the results are shown in Table 1.As shown in Table 1, according to the prior art for preparing ortho-hydroxyanisole, the bis ether by product generates more, and the monoether yield only is 78.0% (embodiment A 1); And the reaction under rare gas element (as nitrogen, argon gas) protection with pyrocatechol and methyl chloride, the monoether yield can improve 7%～9% (embodiment A 2～A3); Partly substitute or replacing whole yellow soda ash with salt of wormwood, the monoether yield can further improve 2%～8%, and (embodiment A 4～A8), when with salt of wormwood replacing whole yellow soda ash, the monoether yield is the highest, reaches 95.0% (embodiment A 8) again.

The preparation condition of table 1 ortho-hydroxyanisole and result

Three, the preparation of 2-ethoxy-phenol

In autoclave, add pyrocatechol 47.1g, toluene 150g and polyoxyethylene glycol 8002.4g, tighten autoclave, vacuumize, in still, charge into rare gas element, (400r/min) slowly adds aqueous solution 50mL, yellow soda ash and/or the wet chemical 80mL that is dissolved with sodium hydroxide 16.1g by discharge port in still under agitation condition again, finish and continue to stir 5 minutes, tighten autoclave, in still, slowly charge into monochloroethane 38.6g, open and stir, be warming up to 140 ℃, reacted 5 hours, be cooled to room temperature, discharging; Reaction solution is transferred in the separating funnel standing demix, collected organic layer and water layer respectively, the organic layer massfraction is that 10% aqueous sodium hydroxide washes is washed (the 1st 150mL 3 times, 2nd, 3 each 50mL), vacuum distillation recovered solvent promptly gets pyrocatechol dme (being bis ether); Alkaline wash and water layer merge, and being neutralized to pH with concentrated hydrochloric acid is 2～3, with 3 times (the 1st 150mL, the 2nd, 3 each 50mL) of toluene extraction, and the combining methylbenzene extraction liquid, vacuum distillation recovered solvent promptly gets ortho-hydroxyanisole (being monoether).

Concrete preparation condition and the results are shown in Table 2.As shown in Table 2, according to the prior art for preparing 2-ethoxy-phenol, the bis ether by product generates more, and the monoether yield only is 80.0% (Embodiment B 1); And the reaction under rare gas element (as nitrogen, argon gas) protection with pyrocatechol and monochloroethane, the monoether yield can improve 6%～7% (Embodiment B 2～B3); Partly substitute or replacing whole yellow soda ash with salt of wormwood, the monoether yield can further improve 1.5%～8%, and (Embodiment B 4～B8), when with salt of wormwood replacing whole yellow soda ash, the monoether yield is the highest, reaches 95.6% (Embodiment B 8) again.

The preparation condition of table 2 2-ethoxy-phenol and result

Explanation is at last, above embodiment is only unrestricted in order to technical scheme of the present invention to be described, although by invention has been described with reference to the preferred embodiments of the present invention, but those of ordinary skill in the art is to be understood that, can make various changes to it in the form and details, and the spirit and scope of the present invention that do not depart from appended claims and limited.

Claims

1. the preparation method of o-hydroxy-phenyl alkyl ether shown in the general formula I is to be starting raw material with halohydrocarbon shown in pyrocatechol and the general formula I I, the Williamson reaction takes place in the presence of alkali and makes:

In general formula I and general formula I I, R is methyl or ethyl, and X is a chlorine or bromine; It is characterized in that: described alkali is the mixture of sodium hydroxide, yellow soda ash and salt of wormwood or is the mixture of sodium hydroxide and salt of wormwood that described being reflected under the protection of inert gas carried out.

2. the preparation method of o-hydroxy-phenyl alkyl ether according to claim 1, it is characterized in that: described alkali is the mixture of sodium hydroxide and salt of wormwood.

3. the preparation method of o-hydroxy-phenyl alkyl ether according to claim 1, it is characterized in that: described rare gas element is nitrogen or argon gas.