JPS6023384A - Method for producing silyl esters of alkylphenols - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a novel method for producing silyl esters of alkylphenols (hereinafter also referred to as alkylsilyl esters).

Conventionally, as a method for producing alkylsilyl esters, a method is known in which alkylphenols are used as a raw material and the alkylphenols are reacted with tetrachlorosilane. However, the above method generally requires complicated reaction operations to obtain the raw material alkylphenols, and in order to obtain alkylsilyl esters in which phenoxy groups are highly alkylated, the number of alkyl groups in the alkylphenols is increased. This method is not necessarily advantageous for industrially producing alkylsilyl esters, as the alkylphenols become solid at room temperature, and the reaction with tetrachlorosilane requires a rise in reaction temperature or a large amount of solvent. There wasn't.

The present invention provides a completely new method for producing alkylsilyl esters, which improves the drawbacks of the conventional methods described above. Third, the present invention is a method for producing silyl esters of alkylphenols, which is characterized by reacting silyl esters of phenols (hereinafter also simply referred to as silyl esters) with an alkylating agent in the presence of a Lewis acid catalyst.

The method of the present invention is very economical because the raw material silyl ester can be easily obtained by reacting phenols with rhodanized silanes or alkoxysilanes, as described below. In addition, even when obtaining an alkylsilyl ester in which the phenoxy group is highly alkylated, since a silyl ester is used as a raw material, the raw material is easier to exist in liquid form than in the conventional method described above, and the reaction is facilitated. can be done. It also has many advantages, such as less solvent usage and, in some cases, no need for it.

In the present invention, silyl esters are particularly limited to those in which 1 to 4 phenoxy groups are bonded to a silicon atom (81,) in the form of a siloxane bond (8j, -0), as shown in the following formula (1). used without.

n (wherein m Fiil is an integer of 3, n is an integer of 0 to 5, X is a substituent, and X/ represents a bonding group with Sl, respectively.

) In formula 11e(I), the number of phenoxy groups may be 1 to 4, but 3 to 4 is particularly preferred in the uses described below. Further, the number of substituents (X) may be 0 to 3, but 0 or 1 is common. The type of substituent (X) is not particularly limited as long as it is stable under the alkylation conditions described below, and includes, for example, an alkyl group having 1 to 6 carbon atoms, a -.logen atom, a nitro group, a lower alkoxy group, etc. However, alkyl groups, V and halogen atoms are particularly preferred. When the number of substituents (X) is plural, each substituent (
X) may be the same or different. In addition, the bonding group (X') bonded to 81 in the formula (I) is not particularly limited as long as it is stable under the alkylation conditions described below, and examples thereof include a halogen atom, an alkyl group, an aryl group, Alkoxy groups are common, and halogen atoms and alkyl groups are particularly preferred.

Examples of silyl esters preferably used in the present invention include cases in which the phenoxy group is an O-flexoxy group (for example, monochloro-tri-0-talesyl silyl ester monobromo-tri-0-clecyl ester). dibrom-di-talesylsilyl ester)
IJ/Loru Mono〇-talesylsilyl ester triflom-mono〇-talesylsilyl ester monomethyl-tri〇-talesylsilyl ester dimethyl-di〇-talesylsilyl ester (5) Monomethyl-mono〇-talesylsilyl ester Examples include ester dimethoxy-di-O-cresylsilyl ester. Examples of the phenoxy group include, in addition to the above-mentioned O-flexoxy group. 79. /ya□ -0(-.

P-flexioxy group -〇be◇-CHj.

m -zfz7z/+&21iii -0°C oath-'P-
Ethylphenoxy group -0→寞)-CH2CH5t(6
) 0-chlorophenoxy group -0-@.

m-/rytv7, :C/Yakker o4t.

P-chlorophenoxy group -Q-@-CA.

0-bromphenoxy group -xb l . -71□yo 71.7 guy-. (f'.

P-bromphenoxy group -04) Br.

0-iodophenoxy group -0%.

. -Yo)” 7:L/Ya, -ozu1.

P-iodophenoxy group -o-@)-x.

0-Fluorophenoxy & -04◇.

. -7-o 7 :c/=P'/'jli
-0,@'.

P-fluorophenoxy group -0-@)-F.

0-nitrophenoxy group. -One. 7.7ya7, -8(-02゜P-nitrophenoxy group -0-@-No2゜○a(3 m-methoxyphenoxy group -0(.

P-ethoxyphenoxy group -0-@-0CH2CH3
.

ρI Silyl esters having the like are also preferably used.

In the present invention, the above-mentioned silyl esters may be used alone or as a mixture of several types of silyl esters.

In addition, the silyl ester can be obtained by any method as long as it has the formula rl as described above. Typical manufacturing methods include tetrachlorosilane, methyltrichlorosilane, dimethyldichlorosilane, Examples include a method of reacting chlorosilanes such as trimethylsilane, alkoxysilanes such as tetramethoxysilane, tetraethoxysilane, and tetrapropoxysilane with phenols. In the above reaction, phenols having a substituent (X) of phenol and fin formula (I) are generally used. For the reaction, known conditions may be employed without particular limitation. Moreover, among the above reactions, industrial Kf& is also preferable, where the reaction between chlorosilanes and phenols is performed. When using the above method with tetrachlorosilane V
A concrete example of C is K as follows.

That is, although it depends on the phenols used, the reaction between phenols and tetrachlorosilane generally proceeds even at room temperature. It is possible to easily produce various silyl esters having different compositions in which 1 to 4 phenoxy groups are substituted, and therefore 6 to 0 un(9)-reactive chlorine atoms are substituted on the S1 atom. In order for the reaction to proceed quickly and efficiently, the reaction is usually carried out at room temperature by mixing tetrachlorosilane with the phenol itself,
Alternatively, it is dropped into a solution of phenols dissolved in a solvent, and then the temperature is gradually raised until the temperature reaches 100%.
A method of heating at several tens to several tens of degrees Celsius for several hours is preferably employed.

Further, in the present invention, as the Lewis acid catalyst, those conventionally used in the Friedel-Crach reaction can be used without particular restriction. For example, aluminum chloride, aluminum bromide, ferric chloride, zinc chloride, stannic chloride, steel chloride.

Metal chlorides such as mercury chloride and titanium tetrachloride are commonly used. Particularly suitable is aluminum chloride. Furthermore, it is preferable that the alkylating agent be one that is difficult to transesterify with the silyl ester under the reaction conditions described below. for example,
Ethylene, propylene, n-7” ten, 1θO-f(1
0) Alkenes such as thene; alkynes such as acetylene and propylene; methyl chloride, ethyl chloride, n-propyl chloride.

180-propyl chloride, IN-butyl chloride, 180-butyl chloride, alkyl chloride, bromides of these alkyls, iodide, fluoride, alkyl halides; allyl chloride,
Those having an alkyl group having 1 to 4 carbon atoms, such as alkenyl halides such as allyl chloride, ethers such as dimethyl ether, diethyl needle, and methyl-8eC-butyl ether, are preferably used.

In the present invention, the silyl ester may be alkylated by carrying out the known Friedel-Crach reaction using the above catalyst and alkylating agent. That is, the temperature of algylation is 0~
400°C, preferably 10-200°C, pressure 0.00
5 to 200 atm, preferably 0.1 to 100 atm.

The reaction time is generally a few minutes to more than ten hours,
It is desirable to carry out alkylation by appropriately determining optimal conditions within the above range. In the above alkylation, the amount of alkylating agent used relative to the silyl ester is adjusted so that the molar ratio of the argyl group of the alkylating agent to the phenoxy group of the silyl ester is 0.1 to 3.0 to reduce byproducts. preferred for. The appropriate amount of the catalyst to be used is 0.1 to 100 mol%, preferably 1 to 50 mol%, and more preferably 5 to 60 mol%, based on the amount of the alkylating agent.

As understood from the above explanation, according to the method of the present invention, alkylsilyl esters can be obtained industrially very advantageously.

The alkylsilyl ester obtained by the present invention is useful as a heating medium, lubricating oil additive, etc., and by hydrolyzing it, alkylphenols useful as intermediates or raw materials for pharmaceuticals, agricultural chemicals, etc. can be produced. It is also possible.

EXAMPLES Below, Examples will be shown to specifically explain the present invention; however, the present invention is not limited to these Examples.

Example 1 A 500*J Mitsuro flask equipped with a cooling tube (cooled with dry ice-methanol), a dropping funnel, and a nitrogen gas introduction tube [0-cresol 524.4 f (5 mol) was charged, and a small amount of l- When heated to a molten state, while introducing nitrogen gas, tetrachlorosilane 85,
Of (0.5 mol) was added dropwise while stirring with a spin bar. Initially, the mixture was reacted for 2 hours at 45-50°C. The temperature was gradually raised and finally heated at 2000°C for 5 hours. After the reaction time, unreacted excess 0-cresol was removed under reduced pressure to obtain 216.4 f of a liquid product. Analysis by gas chromatography confirmed that no unreacted 0-cresol remained. Furthermore, it was confirmed that the element (]3) was an O-talesylsilyl ester represented by the structural formula.

The O-cresylsilyl ester10. Ov (0.088 mol based on 0-cresol), dichloromethane 20rnt as solvent and fi as catalyst, 1cLs 2.3
f (0,018 mol) in the cooling tube.

Pour into a Mitsuro flask with an internal volume of 100 cm equipped with a dropping funnel and a stirrer, and heat in a water bath at 40°C. [While stirring, add 6.9 t of inpropyl chloride (0,088
mol) was added dropwise over 1 hour, and then stirred at the same temperature for 1 hour. Thereafter, the solvent dichloromethane was distilled off under reduced pressure to obtain 15.8 t of residue.

From the results of hydrolyzing a part of this residue and performing gas chromatography and mass spectrometry, it was found that the above residue was obtained by nuclear substitution of the flexioxy group of the raw material 0-cresylsilyl ester with an isopropyl group, and that all flexixi groups were Mono-substituted 68.1%, di-substituted 13.6%, unsubstituted physical strength 1
It was found to be a core inpropylated O(14)-cresylsilyl ester with a composition of 8.3%.

Example 2 A silylation reaction was carried out in exactly the same manner as in Example 1, except that phenol was used at 2°5f (5 mol) for 2 days, yielding 193.1f of a white solid product. G. Analysis by gas chromatography confirmed that no unreacted phenol remained. Furthermore, the results of elemental analysis and C-NMR analysis confirmed that it was a phenylsilyl ester represented by the structural formula S J (0-Q) )4.

The phenylsilyl ester10. Of (110 mol based on phenol), isopropyl chloride 7.9
The alkylation reaction was carried out in exactly the same manner as in Example 1 except that f (0.10 mol) was used [5, remaining 16.
I got 3f. As a result of the same analysis as in Example 1, this residue is one in which the phenoxy group of the raw phenyl cresyl silyl ester has been nuclear-substituted with an inpropyl group, with 49.8 N mono-substituted and 49.8 N di-substituted for all phenoxy groups. It was found that the core was an impropylated phenylsilyl ester with a composition of 20.0% as a substance and 60.2X as an unsubstituted substance.

0-talesylsilyl ester 101 (0-
0.088 mol based on cresol), BF as a catalyst,
etherate 1.2 f (0,008 mol) to 100
- into a stainless steel autoclave, further sealed with 4.9 f (0,087 mol) of 2-butene, and stirred for 2 hours.
The algylation reaction was carried out for 3 hours at 0C. After the reaction, the product in the autoclave was analyzed in the same manner as in Example 1, and it was found that the flexioxy group of the raw material 0-cresylsilyl ester was nuclear-substituted with an 8θC-butyl group, and all flexioxy monosubstituted 89.5X per group,
Nucleus θθ with a composition of 8.4% of disubstituted product 2, IN, and unsubstituted product
It was found to be a C-butylated 0-diylsilyl ester.

Example 4 0-Chlorphenol 192.89 (1.5 mol) Trichlorsilane 85. For (0,5 mol) -
1 Perform the silylation reaction by the same method as in Example 1 [2
Finally, a liquid product of 223°02 was obtained without carrying out the operation of distilling off unreacted O-chlorophenol under reduced pressure. Analysis by gas chromatography confirmed that no unreacted 0-chlorophenol remained, and Alcotra was confirmed with chlorphenylsilyl ester.

MO-chlorophenylsilyl ester io,.

f (0.067 mol based on 0-chlorophenol), FθCLs 2.7 f (0,017 mol) as a catalyst and isobutine 3.7 f (0,06 mol) as an alkylating agent.
The alkylation reaction was carried out at 90°C for 4 hours in the same (1)) reactor as in Example 3.
is. After the reaction, the product in the autoclave was analyzed in the same manner as in Example 1, and it was found that the phenoxy group of the raw material 0-chlorophenylsilyl ester was nuclear-substituted with a t-butyl group, and all phenoxy It was found to be a core t-phthylated O-chlorophenylsilyl ester with a composition of 92.3% mono-substituted and 7.7% unsubstituted.

O-cresylsilyl ester 10f (0.088 mol based on phenol) shown as a catalyst and AlCl2 2
．． The alkylation reaction was carried out in the same manner as in Example 4, except that 7 t (skin 02 mol) and methyl chloride 20.2 f (0.40 mol) were used as the alkylating agent and the reaction time was 6 hours. . After the reaction, the product in the autoclave was analyzed in the same manner as in Example 1. As a result, this product was obtained by further substituting the flexoxy group of the raw material O-cresylsilyl ester (18) with a methyl group. The number of substituents, mainly 2,4,6-trimethyl, is 95.7N for all flexoxy groups.

It was found that the substituent mainly consisting of 2.4-dimethyl is the polysubstituted methylated phenylsilyl ester of 4.5.

Note that the above 2.4.7S-trimethylphenylsilyl ester is replaced by 2.4.6-trimethylphenol (melting point approximately 7
0° C.) and tetrachlorosilane, a considerably large amount of solvent was required, and it was difficult to obtain the desired silyl ester of alkylphenol in the above-mentioned yield.

patent applicant Tokuyama Ichitatsu Co., Ltd. (19) 772-

Claims (1)

[Claims] (],) A method for producing a silyl ester of an alkylphenol, which comprises reacting a silyl ester of a phenol with an alkylating agent in the presence of a Lewis acid catalyst.