JPS61171476A - Novel phenothiazine derivative - Google Patents

Abstract

NEW MATERIAL:The phenothiazine derivative of formula I (X is H or CO-R; R is perfluoroalkyl). EXAMPLE:2-(Perfluoro-octanoyl)-10-(trifluoro-acetyl)phenothiazine. USE:Effective as a cocatalyst for the nucleus-halogenation of an alkylbenzene. The p-site of an alkylbenzene can be selectively halogenated by using 0.001-5.0wt% (based on the alkylbenzene) catalyst consisting of a Lewis acid and the above compound, and introducing a halogenation agent into the system at a temperature lower than the boiling point of the mixture of the alkylbenzene and the catalyst. A p-halogenated alkylbenzene such as p-chlorotoluene useful as an intermediate for pharmaceuticals, agricultural chemicals, etc., can be produced by this process. PREPARATION:The compound of formula I can be produced e.g. by reacting 1mol of phenothiazine with >=1mol of the compound of formula II, preferably under heating.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to novel phenothiazine derivatives. More specifically, the present invention relates to a novel phenothiazine derivative having an effective function as a promoter for nuclear halogenation of alkylbenzene.

Conventional technology Traditionally, phenothiazine derivatives have been used as dyes and pharmaceuticals.

The fact that it is widely used as an insecticide etc.
Although it is known from JP-A No. 21944 and JP-A-57-144270, it has been desired to develop a new phenothiazine derivative having even more excellent activity among these phenothiazine derivatives.

Means for Solving the Problems In view of the above circumstances, the present inventors have conducted extensive research to search for novel phenothiazine derivatives with even more superior activity, and as a result, have discovered a novel compound of the present invention. The present inventors have unexpectedly discovered that phenothiazine derivatives have an effective action as cocatalysts for nuclear halogenation of alkylbenzenes, and have completed the present invention.

That is, the present invention relates to a phenothiazine derivative represented by the general formula (wherein, X represents a hydrogen atom or -Go-R, and R represents a perfluoroalkyl group).

Examples of the phenothiazine derivative represented by the general formula (1) include 10-(perfluoro-octanoyl)phenothiazine and 2-(perfluoro-octanoyl)-10-()lifluoro-acetyl)phenothiazine.

Further, the compound of the present invention can be combined with phenothiazine and the general formula (
n) or (III) (RCO)10-・----m----・-・(n)R
COCl ・−・・−−−−−−−−−・−1111
) (wherein R has the same meaning as above) in an equal or excess amount, and the resulting reaction mixture is post-treated by conventional methods such as liquid separation and washing with water. By doing so, it can be produced with good yield. This reaction generally proceeds conveniently when heated. Although a solvent may not be used, if it is used, it is preferable to use an inert solvent, such as benzene, toluene, xylene, etc.

In addition, by nuclear halogenation of alkylbenzene using the compound of the present invention as a cocatalyst, the P-position can be selectively halogenated, and P-halogens such as P-chlorotoluene, which are useful as intermediates for pharmaceuticals, agricultural chemicals, etc. can produce alkylbenzene.

In order to perform nuclear halogenation of alkylbenzene using the compound of the present invention, a Lewis acid and the compound of the present invention are used as a catalyst in a total amount of 0.001 to 5.0% by weight of the alkylbenzene.
, preferably 0. O is present in a proportion of 1 to 1.0% by weight (Lewis acid and the compound of the present invention are used in a molar ratio of 0.1 to 10:1, preferably 0.25 to 4:1);
By introducing a halogenating agent at a temperature below the boiling point of the mixture with the alkylbenzene, the P-position of the alkylbenzene can be selectively halogenated. If the temperature is too high, the amount of polynuclear halides produced increases and P-
The yield of halide decreases, which is undesirable.On the other hand, the reaction can be carried out at a low temperature of -10°C or lower, and the selectivity of P-halide increases, but the reaction rate is slow and uneconomical, so it is usually carried out at temperatures of 0 to 100°C. temperature, industrially 20-70
Preferably, it is carried out at .degree.

The Lewis acids used in this reaction are not only Lewis acids in the usual sense, but also Lewis acids during nuclear halogenation.
(Metals or compounds that form Lewis acids or function as Lewis acids, such as antimony, iron, tin, lead, aluminum, molybdenum, tellurium, etc.); halides and oxides of these metals; compounds, sulfides, and carbonyl compounds.

Particularly preferred examples include antimony trichloride, antimony pentachloride, aluminum chloride, antimony trifluoride, ferrous chloride, ferric chloride, antimony oxychloride, antimony dioxide, antimony tetroxide,
Examples include antimony pentoxide, tellurium tetrachloride, ferric oxide, lead sulfide, ferrous sulfide, iron disulfide, molybdenum hexacarbonyl, and iron pentacarbonyl.

Further, as the halogenating agent used in this reaction, a commonly used halogenating agent can be used, but chlorine gas, sulfuryl chloride, bromine, etc. are preferably used.

Effects of the Invention By using the novel phenothiazine derivative of the present invention as a cocatalyst for the nuclear halogenation reaction of alkylbenzene, it suppresses halogenation at the ○-position of alkylbenzene and
It has the advantage that the - position can be selectively and efficiently halogenated, and that side chain halides and polynuclear halides of alkylbenzene such as benzyl halide are extremely less produced. Furthermore, P
- Suitable for producing halogenated alkylbenzenes.

Example The present invention will be explained in more detail below using Examples.

Example 1 Method for Preparing 10-(Perfluoro-octanoyl)phenothiazine Into a 200+w1 reaction flask equipped with a condenser, thermometer, and stirrer, 0.4 g (2,0 mmol) of phenothiazine was added.
), perfluoro-octanoic anhydride 1.66 g (
2, Oav+ol) and 10 ml of benzene were added and reacted at 80 to 90° C. for 44 hours with stirring. After cooling, post-treatment is performed to obtain 10-(perfluoro-
0.83 g of crystals of (octanoyl)phenothiazine were obtained.

Identification data is shown below.

I R (K B r cab-'); 1680.1
190.1140.760 Reference Example 1 Method for producing 2-(perfluoro-octanoyl)phenothiazine 4.14 g (10-mol) of Perf J rheoloctanoic acid was placed in a 100+1 flask equipped with a condenser, thermometer, and stirrer.
+4.26 g (30 mmol) of phosphorus pentoxide and 30-1 of benzene were added and heated to 80 to 90° C. for 4 hours with stirring.

Furthermore, phenothiazine 1.99g (1G +
u+ol) was added and reacted by heating at 95°C for 22 hours.
After the reaction was completed, water was added and the mixture was extracted with methylene chloride, the solvent was removed, and the mixture was recrystallized with methanol to obtain 4 g of white granular crystals of 2-(perfluoro-octanoyl)phenothiazine.

Identification data is shown below.

IR(KB rcm-Re:3140(-NH)J:1
680(C-0), 5:1200-1140(F)
, S Example 2 Method for producing 2-(perfluoro-octanoyl)-10-(trifluoro-acetyl)phenothiazine In a 20-l flask equipped with a condenser, thermometer, and stirrer, 2-( obtained in Reference Example 1) was added. Add 1.20 g (2 mmol) of perfluoro-octanoylphenothiazine, 0.84 g (4+u++ol) of trifluoroacetic anhydride, and 10 ml of benzene, and heat the reaction at 40 to 42°C for 21 hours with stirring. After the reaction is complete, water is added. After extraction with methylene chloride, removing the solvent and recrystallizing with methanol, 2-(perfluoro-octanoyl") -10-
1.18 g of white granular crystals of ()lifluoro-acetyl)phenothiazine were obtained.

Identification data is shown below.

I R (KBr cm-'); 1680 (C-0), 5
1480.1460.1440(-Ph), m~S;1
350, m 1200-1140 (F), S Example 3゛200w1 equipped with cooling tube, temperature needle, stirrer, blowing tube
Into the reaction flask, add 0.23 g of antimony trichloride (1
Add 0.6 g (1-mol) of 10-(perfluoro-octanoyl)phenothiazine and 92 g (1 mol) of toluene, and stir at 30°C under a stream of N for 30 minutes. Continued to be 0
．． The reaction was carried out by blowing chlorine at 5 aol/hour for 1 hour. After the reaction was completed, the resulting reaction solution was analyzed by gas chromatography, and the composition of the monochlorotoluene produced was 0-chlorotoluene/P-chlorotoluene ratio (hereinafter referred to as O/P) -0.8.

Example 4 The reaction was carried out in the same manner as in Example 3 except that 2-(perfluoro-octanoyl)-10-(trifluoro-acetyl)phenothiazine was used instead of 10-(perfluoro-octanoyl)phenothiazine in Example 3. However, the O/P was -0.81.

Claims (1)

[Claims] A phenothiazine derivative represented by the general formula ▲ Numerical formula, chemical formula, table, etc. ▼ (wherein, X represents a hydrogen atom or -CO-R, and R represents a perfluoroalkyl group).