JPH09227439A - Aldehyde formation - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a new method for preparing an aldehyde, capable of effectively converting an aldehyde precursor to the aldehyde under a mild condition. SOLUTION: A trifluoromethanesulfonic acid ester is treated with a silicon hydride as a proton source in the presence of a catalyst by using carbon monoxide as a carbon source.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a chemical reaction in an organic compound, particularly to a method for aldehyde formation,
Therefore, it can be widely used when introducing an aldehyde group into an organic compound.

[0002]

2. Description of the Related Art The Gattermann-Koch method is a well-known method for introducing an aldehyde group into an aromatic hydrocarbon using carbon monoxide as a carbon source. In this method, the yield in the high pressure reaction is good, but the yield in the normal pressure is low. There is also a method of reductively converting the unsaturated compound into a terminal aldehyde using carbon monoxide, hydrogen and a cobalt catalyst.
The toxicity of cobalt carbonyl compounds has been pointed out.

There has been proposed a method for producing an aldehyde compound by using carbon monoxide and tin hydride in the presence of an organic halogenated compound as a catalyst. This is an aryl iodide,
Benzyl halide, vinyl iodide, allyl halide, etc. are reacted with carbon monoxide, tin hydride and palladium catalyst to convert halogen atom to aldehyde group (CHO).
Is converted to Here, a triflate compound in which a trifluoromethylsulfinyloxy group is substituted instead of a halogen atom, for example, 4-t-butyl-1-
A similar formylation of cyclohexenyl triflate has been revealed (J. Am. Chem, S.
oc. , 1986, 108, 452-461). However, in order to obtain the target product in good yield, pressurization is required and it must be improved.

[0004]

DISCLOSURE OF THE INVENTION The present invention provides a novel method for converting a triflated compound into an aldecht compound using carbon monoxide as a carbon source and silicon hydride as a proton source.

[0005]

Means for Solving the Problems A triflated compound is suspended in a solvent together with a catalyst and heated to introduce carbon monoxide. Then, silicon hydride is added and reacted. Here, the triflated compound may be an aryl triflate, an enol triflate, or an aliphatic hydrocarbon triflate and may be of any kind. Specific examples are phenyl triflate, naphthyl triflate, quinolyl triflate, cyclohexene triflate, cyclooctene triflate, cyclopentene triflate, butane triflate, hexane triflate, pentane triflate, hexane triflate, octane triflate, and the like. These can be the subject of the present invention even if they have a substituent as well as those not having a substituent.

Next, those used as catalysts are palladium acetate, nickel acetate, etc. and 1,3-bisdiphenylphosphinopropane and 1,1 'which are ligands.
-A complex compound with bisdiphenylphosphinoferrocene or the like is used. Since such a complex compound can be formed in the reaction system, preparation in advance is not excluded, but preparation in particular is not necessary.

The solvent used is not particularly limited as long as it does not participate in the reaction, but preferably N, N-dimethylformamide, dimethylsulfoxide, triethylamine, pyridine, dimethylaniline,
Examples thereof include ethyl ether and isopropyl ether. The reaction is allowed to proceed at room temperature and under heating, but it is similar to a general chemical reaction that the application of heat accelerates the reaction.

When carbon monoxide is introduced at atmospheric pressure, the introduction of the carbon monoxide causes a marked change in the hue of the reaction system. At that time, the necessary amount of carbon monoxide is satisfied. , Stop the introduction.

Examples of the silicon hydride as a proton source include trialkylsilanes such as triethylsilane, tributylsilane, trihexylsilane, trioctylsilane and dimethylphenylsilane. Conveniently, these are dissolved in the above-mentioned solvent and used for the reaction.

The aldehyde compound thus produced in the system is obtained by extraction with ether, ester, hexane, benzene, toluene, etc. in a conventional manner.

[0011]

The method of the present invention will be described in detail below with reference to specific examples, but the present invention is not influenced thereby. Example 1 4-t-butylphenyl trifluorosulfonate 1 m
mol, palladium (II) acetate 0.02 mmol,
1,3-bis (diphenylphosphino) propane 0.0
A mixture of 2 mmol and 5 ml of dimethylformamide was heated to 70 ° C. with stirring, and then carbon monoxide was bubbled in for 20 minutes. At this point, the color of the solution changed significantly from light brown to dark brown. Therefore, 2.0 mmol of trioctylsilane and 2.5 mmol of triethylamine were added dropwise using a microsyringe. Then at the same temperature,
Stirring was continued until there was no TLC detection of the starting compound.
Water was added to the reaction solution, and the mixture was extracted with ether. The extracts were collected, washed with water, washed with saturated aqueous sodium hydrogen carbonate and saturated brine in that order, dried over sodium sulfate, and concentrated. The crude product was purified by column chromatography to give 4-t-butylbenzartehde. Reaction yield 89%

Example 2 2-Naphthyl triflate 1 mmol Palladium (II) acetate 0.03 mmol, 1,3-bis (diphenylphosphino) propane 0.02 mmol, 5 ml of dimethylformamide were stirred and heated to 70 ° C. After that, carbon monoxide was bubbled in for 20 minutes. At this point, the color of the solution changed significantly from light brown to dark brown. Therefore, 2.0 mmol of trioctylsilane and 2.5 mmol of triethylamine were added dropwise using a microsyringe. Then, stirring was continued at the same temperature for 3.5 hours. Water was added to the reaction solution, and the mixture was extracted with ether. The extracts were collected, washed with water, washed with saturated aqueous sodium hydrogen carbonate and saturated brine in that order, dried over sodium sulfate, and concentrated. The crude product was purified by column chromatography to give 2-naphthyl aldehyde. 94% yield

Example 3 In Example 2, 1,3-bis (diphenylphosphino) propane was replaced with 1,1-bis (diphenylphosphino).
In place of ferrocene, trioctylsilane and triethylamine were added over 25 minutes, and the reaction was stopped immediately, to obtain 2-naphthylaldehyde in the same manner as in Example 2. Yield 89%

Examples 4 to 10 In the same manner as in Example 1 except that the raw material compound 4-t-butylphenyltrifluorosulfonate used in Example 1 was replaced by the compounds shown in Table 1, the corresponding artehydride compounds were obtained. It was The raw material name, product name, yield, etc. are shown in Table 1.

[Table 1]

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[Procedure amendment]

[Submission date] June 26, 1996

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Name of invention

[Correction method] Change

[Correction contents]

Title of the invention Aldehylation method

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical indication location C07C 47/544 9049-4H C07C 47/544 47/546 9049-4H 47/546 47/575 9049- 4H 47/575 67/313 67/313 69/757 69/757 C 69/76 69/76 Z C07D 239/26 C07D 239/26 317/60 317/60 // C07B 61/00 300 C07B 61/00 300

Claims (2)

[Claims] 1. A method for converting a triflated moiety into an aldehyde, which comprises reacting a triflated compound with carbon monoxide as a carbon source and silicon hydride as a proton source in the presence of a catalyst. . 2. The method according to claim 1, wherein the triflated compound according to claim 1 is an α, β-unsaturated triflate compound.