KR900006129B1 - Method for preparing carbonyl compound - Google Patents

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Description

Method for preparing carbonyl compound

The present invention relates to a new and advanced process for preparing carbonyl compounds of the following general formula (I) from thiocarbonyl compounds of the following general formula (II).

In general formula (I), R <^1> represents alkyl, substituted or unsubstituted phenyl, alkoxy, substituted or unsubstituted phenoxy group. R ² represents substituted or unsubstituted aniline, secondary or tertiary amine. R ¹ and R ² may be the same or different. However, when R ¹ is a substituted or unsubstituted phenoxy group, R ² is a secondary or tertiary amine, or represents a substituted or unsubstituted thiophenoxy group.

In the formula (II), R ¹ and R ² are the same as each other and R ¹ and R ² in the formula (I). In many cases, the carbonyl group is an important functional group included in the structure of complex organic compounds such as pharmaceuticals and pesticides. When thiocarbonyl derivatives can be easily synthesized, first, after the synthesis of the thiocarbonyl compound, Thiocarbonyl compounds can be effectively converted to the corresponding carbonyl compounds.

The object of the present invention and its actions and effects are as follows. A thiocarbonyl compound of the general formula (II) is reacted with a thinitrate of the general formula (III) in an organic solvent under mild reaction conditions. To prepare a carbonyl compound. The reaction feature of the present invention is to easily remove sulfur from the thiocarbonyl compound of the general formula (II) to produce the carbonyl compound of the present invention.

R ³ in the general formula (III) is a tertiary alkyl group such as tertiary butyl, tertiary pentyl or 1,1-dimethyl heptyl group, which may be used, but it is particularly stable that tertiary butyl is used for reaction. easy.

Tertiary alkyl thionite compounds of formula (III) can be readily obtained by reacting tertiary alkyl mercaptans with excess dinitrogen tetraoxide (N ₂ O ₄ ) [Bull. Chem. Soc. Jpn., 53, 775 (1980)], the present inventors can use this tertiary alkyl thioniteate to nitrosify the sulfur atom of the thiocarbonyl compound, and then to remove the sulfur to react with the carbonyl compound very effectively. It was found that the present invention was completed.

In general, a known manufacturing method for preparing a carbonyl compound corresponding to the thiocarbonyl compound by leaving sulfur by a nitrosification reaction, using sodium nitrite (NaNO ₂ ) in an acidic aqueous solution at room temperature or [Tetrahedron 38, 1163 (1982)], N-methyl-N-nitroso aniline or N-nitroso piperidine and potassium iodide in acidic aqueous solution at room temperature [Tetrahedron 39, 469 (1983)]. However, these conventional methods not only have a longer reaction time than the yield, but also require a reaction in an acidic aqueous solution. Thus, when the compound to be reacted or the compound to be obtained is unstable in an acidic aqueous solution or when a compound having low solubility in water is used. It is inconvenient to use these methods. However, the present invention can not only react in anhydrous organic solvent, but also the reaction conditions are neutral, so that the problems in the known production methods can be solved, and the reaction time is short and the yield is very high even at low temperature. It is an advantage.

According to the method of the present invention, the sulfur elimination reaction is carried out in the reaction of the thiocarbonyl compound of the general formula (II) with the tertiary alkyl thinitrate of the general formula (III) in the presence of an organic solvent at a temperature of -10 ° C to 25 ° C. By reacting, it can advance in minutes. Subsequently, by separating and recovering the reaction solvent, the carbonyl compound of the general formula (I) can be obtained in high yield. At this time, the released sulfur is mostly converted to sulfur molecules (S ₈ ) situation is removed. The organic solvent used in the present invention may be any solvent that is well soluble in the starting material in an aprotic solvent such as acetonitrile, tetra hydrofuran, chloroform, dichloromethane.

In the present invention, in the case where alkyl is butyl in the tertiary alkyl thionate of general formula (III), the tertiary butyl thionitriate is represented by the following general formula (IV) and general formula (V) Thioca of formula (II) if rearrangement is possible

The carbonyl compound is reacted with a compound of the general formula (V), which is a rearranged form of thionite, to introduce a nitroso group to the sulfur atom of the thiocarbonyl group to form a nitroso intermediate. It is assumed that the carbonyl compound is formed. If the mechanism of this reaction process is represented by chemical reaction equation, it is judged that the reaction will proceed as follows.

The objects, operations and effects of the present invention will become more apparent from the following examples.

Example 1

[Production of 4- (P-nitro benzoyl) morpholine]

To a solution of 4- (P-nitrothiobenzoyl) morpholine (2.52 g, 100 mmol) in anhydrous dichloromethane (50 ml) was added tert-butyl thionitrate (100 mmol), followed by stirring at 0 ° C. for about 10 minutes. Let's do it. The reaction mixture was filtered to remove sulfur, and the filtrate was concentrated under reduced pressure (20-30 mmHg), followed by silica gel column chromatography (CHCl ₃ / MeOH 20/1) to obtain 4- (p-nitro benzoyl) morpholine (2.31 g, Yield 98%) Melting point: 101-104 ℃

Example 2

[Preparation of N-p-chlorophenyl acetamide]

To a solution of Np-chloro phenyl thioacetamide (464 mg, 25 mmol) in anhydrous chloroform (15 ml) was added tertiary butyl thionite (25 mmol), followed by stirring at 50 ° C. for about 15 minutes. The reaction mixture was filtered and the filtrate was concentrated under reduced pressure and purified by silica gel column chromatography (CHCl ₃ / MeOH = 15/1) to give Np-chloro phenyl acetamide (349 mg, 82% yield). Melting Point: 175-177 ° C.

Example 3

[Preparation of N-p-nitrophenyl acetamide]

To a solution of Np-nitrophenylthioacetamide (830 mg, 5 mmol) in anhydrous acetonitrile (10 ml) was added tertiary pentyl thionite (5 mmol), followed by stirring at 7 ° C. for about 10 minutes. The reaction mixture was filtered and the filtrate was concentrated under reduced pressure and purified by silica gel column chromatography (CHCH ₂ / MeOH-15-1) to afford the title compound Np-nitrophenyl acetamide (765 mg, 85% yield). Melting point: 213-215 ° C.

Example 4

[Production of N-phenyl Benzamide]

To a solution of N-phenyl thiobenzamide (1.06 g, 50 mmol) in anhydrous acetonitrile (30 ml) was added tertiary 1,1-dimethyl heptyl thionite (50 mmol), followed by stirring at 4 ° C. for about 10 minutes. Let's do it. The reaction mixture was filtered and the filtrate was purified by silica gel column chromatography (CHCl ₃ ) to afford the title compound N-phenyl benzamide (0.74 g, 76% yield). Melting point: 161-163 ° C.

Example 5

[Production of N-n-propyl benzamide]

To a solution of Nn-propyl thiobenzamide (156.5 mg, 0.873 mmol) in anhydrous acetonitrile (4 ml) was added tert-butyl thionite (0.873 mmol), followed by stirring at 0 ° C. for about 15 minutes. The reaction mixture was filtered and the filtrate was concentrated under reduced pressure and purified by silica gel column chromatography (CHCl ₃ / MeOH = 15/1) to give the title compound N-propyl benzamide (124.2 mg, 87% yield). Melting point: 77-79 ° C.

Example 6

[Production of benzophenone]

To a solution of thio benzophenone (1.0 g, 50.5 mmol) in anhydrous acetonitrile (30 ml) was added tert butyl thionite (50.5 mmol), followed by stirring at 0 ° C. for about 10 minutes. The reaction mixture was filtered and the filtrate was concentrated under reduced pressure and purified by silica gel column chromatography (n-hexane / CH ₂ Cl ₂ = 3/2) to obtain the title compound benzophenone (0.86 g, 93% yield). Melting point: 47-48 ° C.

Example 7

[Preparation of O-Methyl-N-phenyl Carbamate]

To a solution of O-methyl-N-phenyl thiocarbamate (420 mg, 25 mmol) in anhydrous acetonitrile (10 ml) was added tert-butyl thionite (25 mmol), followed by stirring at 0 ° C. for about 1 hour. Let's do it. The reaction mixture was filtered, the filtrate was concentrated under reduced pressure and purified by silica gel column chromatography (n-hexane / CH ₂ Cl ₂ = 3/2) to give the title compound O-methyl-N-phenyl carbamate (357 mg, yield). 95%). Melting point: 43-46 ° C.

Example 8

[Preparation of morpholine thiocarboxylic acid S-p-chloro phenyl ester]

To a solution of morpholine dithio carboxylic acid p-chloro phenyl ester (1.0 g, 36.5 mmol) in anhydrous acetonitrile (30 ml) was added tert butyl thionite (36.5 mmol), followed by stirring at 0 ° C. for about 15 minutes. Let's do it. The reaction mixture is filtered and the filtrate is purified by silica gel column chromatography (CHCl ₃ ) to afford the title compound morpholine thiocarboxylic acid Sp-chloro phenyl ester (0.91 g, 95% yield). Melting point: 104-108 ° C.

Example 9

[Preparation of S, S-di-p-tolyl dithiocarbonate]

To a solution of di-p-tolyl trithio carbonate (700 mg, 2.41 mmol) in anhydrous acetonitrile (15 ml) was added tert butyl thionyrate (2.41 mmol), followed by stirring at 25 ° C. for about 5 hours. . The reaction mixture was filtered, the filtrate was concentrated under reduced pressure, and purified by silica gel column chromatography (n-hexane / CH ₂ Cl ₂ = 2/3) to give the title compound S, S-di-p-tolyl dithio carbonate. (594 mg, yield 90%) is obtained. Melting point: 90-92 ° C.

Although the method of the present invention has been described by way of example the most preferred embodiment, the present invention is not limited thereto, and appropriate modifications and changes are possible by those skilled in the art within the scope of protection of the present invention. It is feed.

Claims (3)

A process for producing a carbonyl compound, wherein the thiocarbonyl compound of the general formula (II) and the tertiary alkyl thionite of the general formula (III) are reacted in the presence of an organic solvent.

In general formula (I), R <^1> represents alkyl, substituted or unsubstituted phenyl, alkoxy, substituted or unsubstituted phenoxy group. R ² represents substituted or unsubstituted aniline, secondary or tertiary amine. R ¹ and R ² may be the same or different. However, when R ¹ is a substituted or unsubstituted phenoxy group, R ² represents a secondary or tertiary amine, or represents a substituted or unsubstituted thiophenoxy group. In the formula (II), R ¹ and R ² are the same as each other and R ¹ and R ² in the formula (I). In General Formula (III), R ³ represents tertiary butyl, tertiary pentyl or 1,1-dimethylheptyl group. The method for producing a carbonyl compound according to claim 1, wherein the organic solvent is used singly or in combination of two or more of acetonitrile, tetrahydrofuran, chloroform and dichloromethane. The method for producing a carbonyl compound according to claim 1, wherein the reaction is carried out at a reaction temperature of -10 ° C to 25 ° C.