JP2000256344A - Alpha-pyrone compound and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject new compound useful as a raw material for synthesizing medicaments/agrochemicals by synthesis using a readily available halogeno alkenoic ester as the starting material. SOLUTION: This new compound is an α-pyrone compound of formula I (R1 is a univalent hydrocarbon; X is a halogen; R3 and R4 are each a univalent hydrocarbon, heterocyclic aromatic ring or silyl), e.g. 4-butyl-5,6-dipropyl-2H- pyran-2-one. The compound of formula I is obtained, for example, by reaction of a 3-halogeno-2-alkenoic ester of formula II (R2 is a univalent hydrocarbon; X is a halogen, pref. Cl) with an acetylene compound of formula III in the presence of a group X metal-contg. catalyst, wherein the group X metal in the catalyst is pref. palladium, and the above reaction is carried out pref. in the presence of an organic base (pref. a trialkylamine), thereby efficiently and safety affording the objective compound.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a novel alpha-pyrone and a novel method for producing an alpha-pyrone by reacting a 3-halogeno-2-alkenoic acid ester with an acetylene compound. The alpha-pyrones provided by the present invention are a group of compounds useful for producing fine chemicals such as medical and agricultural chemicals.

[0002]

2. Description of the Related Art Alpha-pyrones are generally produced by a condensation reaction of a beta keto ester, a condensation reaction of an acetylene ketone and a malonic ester, a condensation reaction of an enone and a diazo ester, and the like. Further, a method of reacting acetylenes with carbon dioxide in the presence of a complex catalyst and a method of carbonylating cyclopropenyl ester or cyclopropenyl ketone using a rhodium catalyst are also known.
However, there is no known method for obtaining alpha-pyrones by using a readily obtainable 3-halogeno-2-alkenoic acid ester as a starting material. The 4,5,6-substituted pyrones related to the present invention are novel compounds, and their production examples are not known.

[0003]

The present invention relates to 3-halogeno-2-alkenoic acid esters, preferably 3-chloro-alkenoic acid esters.
It is an object of the present invention to provide a novel and efficient method for producing alpha-pyrones using a 2-alkenoic acid ester as a starting material, and a 4,5,6-substituted alpha-pyrones thereby.

[0004]

Means for Solving the Problems The present inventors have made intensive studies to solve the above-mentioned problems, and as a result, in the presence of a Group 10 metal-containing catalyst, 3-halogeno-2-alkenoic acid ester was converted to an acetylene compound. And easily found the novel fact of giving alpha-pyrones, based on which the present invention was completed.

That is, according to the present invention, 3-halogeno-2-
A process for producing alpha-pyrones, which comprises reacting an alkenoic acid ester with an acetylene compound in the presence of a palladium catalyst and an organic base, and a novel 4,5,6-substituted alpha-pyrones thereby provided. .

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The 3-halogeno-2-alkenoic acid ester used as a raw material in the present invention has the general formula (1)

Embedded image (Wherein, R ¹ and R ² represent the same or different monovalent hydrocarbon groups, and X represents a halogen atom).

The acetylene compound used in the present invention has a general formula (2)

Embedded image (Wherein, R ³ and R ⁴ represent the same or different monovalent hydrocarbon group, heteroaromatic ring group, or silyl group).

[0008] The monovalent hydrocarbon group of the present invention has 1 to 30 carbon atoms, preferably 1 to 20 carbon atoms, more preferably 1 to 20 carbon atoms.
10 linear or branched alkyl groups, having 2 to 3 carbon atoms
0, preferably 2 to 20, more preferably 2 to 10, linear or branched aliphatic hydrocarbon groups such as alkenyl groups and alkynyl groups, 5 to 30 carbon atoms, preferably 5 to 2 carbon atoms.
0, more preferably 6 to 10 monocyclic, polycyclic or fused cyclic saturated or unsaturated alicyclic hydrocarbon groups, 6 to 3 carbon atoms
0, preferably 6 to 20, and more preferably 6 to 10 monocyclic, polycyclic or condensed cyclic aromatic hydrocarbon groups. Further, the above-mentioned aliphatic hydrocarbon group may be substituted with the above-mentioned alicyclic hydrocarbon group or aromatic hydrocarbon group, and the above-mentioned alicyclic hydrocarbon group is the above-mentioned aliphatic hydrocarbon group or It may be substituted with an aromatic hydrocarbon group, and the above-mentioned aromatic hydrocarbon group may be substituted with the above-mentioned aliphatic hydrocarbon group or alicyclic hydrocarbon group.

As the halogen atom of the general formula (1), the desired 4,5,6-
What is necessary is just to generate substituted alpha-pyrones,
Preferably they are chlorine, bromine and iodine, more preferably a chlorine atom. Preferred compounds represented by the general formula (1) of the present invention include the following formula (4):

Embedded image (In the formula, R ¹ and R ² represent the same or different monovalent hydrocarbon groups.) 3-chloro-2-alkenoic acid ester represented by the formula:

Examples of the hydrocarbon groups R ¹ and R ^{2 in} the general formula (1) or (4) include methyl, ethyl, isopropyl, pentyl, octyl, phenyl, naphthyl, benzyl And a phenethyl group. Therefore, examples of the 3-chloro-2-alkenoic acid ester represented by the general formula (4) having such a hydrocarbon group include (Z) -3-methyl-2-chloro-2-heptenoate, (Z) -3 -Chloro-4,4-dimethyl-
Methyl 2-pentenoate, (Z) -3,6-dichloro-2
-Methyl hexenoate, methyl (Z) -3-chloro-4-methoxy-2-butenoate, methyl (Z) -6-cyano-3-chloro-2-hexenoate, (Z) -3-chlorocinnamic acid Methyl, methyl (Z) -3-chloro-p-methylcinnamate, methyl (Z) -4-phenyl-3-chloro-2-butenoate, methyl (Z) -3-chloro-2-nonenoate,
(Z) -7- [dimethyl (t-butyl) siloxy] -3
Methyl-chloro-2-heptenoate, methyl (Z) -3-chloro-p-chlorocinnamate, (Z) -3-chloro-2-
Ethyl heptenoate, benzyl (Z) -3-chloro-2-heptenoate, phenyl (Z) -3-chloro-2-heptenoate, p-bis [{(Z) -1-chloro-2-methoxycarbonyl} Ethenyl] benzene, (Z) -3- (1-
Cyclohexenyl) -3-methyl chloroacrylate,
(Z) -3-Chloro-2,4-pentadienoic acid methyl and the like are exemplified.

The heteroaromatic group of the present invention has at least one nitrogen atom, oxygen atom or sulfur atom in the ring and has a ring size of 5 to 20 members, preferably 5 to 1 member.
A 0-membered, more preferably 5 to 7-membered, monocyclic, polycyclic or condensed cyclic heteroaromatic ring group is preferable, and the heteroaromatic ring group may have a substituent. Examples of the substituent include the above-described aliphatic hydrocarbon group, alicyclic hydrocarbon group, and aromatic hydrocarbon group. Further, as the silyl group of the present invention, a silyl group substituted with a monovalent hydrocarbon group or a heteroaromatic ring group described above is preferable, for example, a trialkylsilyl group, a triphenylsilyl group, an aryldialkylsilyl group. And a trialkoxysilyl group.

In the general formula (2) of the present invention, the groups R ³ and R
Examples of ⁴ include a methyl group, an ethyl group, an isopropyl group, a pentyl group, an octyl group, a phenyl group, a naphthyl group, a benzyl group, a phenethyl group, a furyl group, a thienyl group, a trimethylsilyl group and the like. Also, R ³ ,
R ⁴ may be one in which a functional group is bonded to these hydrocarbon group, heteroaromatic ring group, or silyl group. Therefore, as the acetylene compound represented by the general formula (2), 2-butyne, 3-hexyne, 4-octyne,
Examples include phenylmethylacetylene, 1- (p-methoxyphenyl) -1-butyne and the like.

The acetylene compound represented by the general formula (2) used in the reaction is 3-substituted-2 represented by the general formula (1)
The molar ratio with respect to the -alkenoic acid ester can be arbitrarily selected, but considering the yield with respect to the 3-substituted-2-alkenoic acid ester, is preferably 1 or more with respect to the 3-halogeno-2-alkenoic acid ester, Usually it is 1-2.

The reaction of the present invention is carried out in the presence of a Group 10 metal containing catalyst. As used herein, the family numbers in the periodic table are based on IUPAC Inorganic Chemical Nomenclature Revised Edition (1989).
It is based on. Examples of the Group 10 metal include palladium, nickel, platinum and the like. Palladium and nickel are preferable, and particularly in the case of palladium, the reaction proceeds efficiently. As the palladium-containing catalyst, various catalysts including conventionally known ones such as a metal complex, a metal salt, a metal and a supported metal can be used. Specific examples thereof include dichloro (1,5-cyclooctadiene) palladium, bis (dibenzylideneacetone) palladium,
Tris (dibenzylideneacetone) dipalladium, dichlorobis (benzonitrile) palladium, dibromobis (benzonitrile) palladium, dichlorobis (acetonitrile) palladium, di-μ-chlorobis (π-allyl) dipalladium, dichlorobis (pyridine) palladium, dichlorobis ( Triphenylphosphine) palladium, diiodobis (dimethylphenylphosphine) palladium, dichlorobis (triethylphosphine) palladium, dichlorobis (trimethylphosphine) palladium, dichlorobis (trimethylphosphite) palladium, dibromo (triisopropylphosphite) palladium, dichlorobis (triphenylphosphine) Phyto) palladium, dichlorobis (dimethoxyethylphosphine)
Examples include palladium, dichloro [1,4-bis (diphenylphosphino) butane] palladium, tetrakis (triphenylphosphine) palladium, palladium acetate, palladium chloride, palladium iodide, and palladium on activated carbon. As the nickel-containing catalyst, various phosphine nickel complexes are preferable. These catalysts
Two or more of them can be used in combination, or a ligand such as triphenylphosphine, 1,1′-bis (diphenylphosphino) ferrocene, or trimethylolpropane phosphite can be used in combination.

The molar ratio of the catalyst of the present invention to the 3-substituted-2-alkenoic acid ester or acetylene compound can be arbitrarily selected, but is usually in the range of 0.0001 to 0.5.

The reaction of the present invention is promoted by adding an organic base. As the organic base used, primary, secondary or tertiary amines are generally used, but aliphatic or cycloaliphatic tertiary amines are preferred. Examples thereof include triethylamine, tributylamine, dicyclohexylmethylamine, N-methylpyrrolidine, 1,8-diazabicyclo [5.4.
0] undec-7-ene (DBU). The molar ratio of the base to the 3-halogeno-2-alkenoic acid ester is preferably 1 or more, and usually 1 to 10, in consideration of the yield of the generated pyrones.

The reaction of the present invention is carried out at a reaction temperature of -20 ° C or higher, preferably 0 to 200 ° C. In addition, the method of the present invention can be carried out with or without a solvent, but when a solvent is used, other than a hydrocarbon solvent such as benzene, toluene, xylene, hexane, and decalin and an ether solvent such as dibutyl ether, a raw material Various organic solvents except those that react with the 3-halogeno-2-alkenoic acid ester or the acetylene compound can be used.

The separation and purification of the desired product from the reaction mixture can be easily achieved by means commonly used in organic chemistry such as distillation, chromatography or recrystallization. On the other hand, the novel 4,5 provided by the present invention
The 6-substituted alpha-pyrones have the general formula (3)

Embedded image (Wherein R ¹ , R ³ , and R ⁴ are the same as described above), and specifically, 4-butyl-5,6-dipropyl-2H -Pyran-
2-one, 4-butyl-5,6-diethyl-2H-pyran-2-one, 4-butyl-5-methyl-6-ethyl-
2H-pyran-2-one, 4-butyl-5-ethyl-6
-Methyl-2H-pyran-2-one, 4-hexyl-
5,6-dipropyl-2H-pyran-2-one, 4-
(3-cyanopropyl) -5,6-dipropyl-2H-
Pyran-2-one, 4-phenyl-5,6-dipropyl-2H-pyran-2-one, 4- (3-chloropropyl) -5,6-dipropyl-2H-pyran-2-one,
4-butyl-5-ethyl-6-phenyl-2H-pyran-2-one, 4-butyl-5-trimethylsilyl-6
Phenyl-2H-pyran-2-one and the like are exemplified.

[0019]

Next, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.

Example 1 (Z) -3-chloro-2 was placed in a thick Pyrex reaction tube.
-Methyl heptenoate (0.5 mmol), 4-octyne (0.6
mmol), triethylamine (2.5 mmol), dichlorobis (triphenylphosphine) palladium (0.025 mmol) and toluene (1.0 mL) were charged into a nitrogen stream, sealed, and reacted at 120 ° C. for 20 hours to obtain ammonium. A precipitate that appears to be salt forms. After cooling, low-boiling substances were distilled off under reduced pressure, and the residue was extracted with hexane (5.0 mL).
After concentrating to about 1 mL, analysis by gas chromatography revealed that 4-butyl-5,6-dipropyl-2H
It was found that -pyran-2-one (2a) was produced in a yield of 83%. Further, by separation and purification by column chromatography (alumina column, elution with hexane), 4-butyl-5,6-dipropyl-2H-pyran-2-one was converted to a colorless oil with a 74% isolated yield. Obtained. This compound was a novel compound not described in any literature, and its physical properties and spectrum data were as follows.

Boiling point: 120 ° C./0.9 mmHg (Kugel roll). ¹ H-NMR (C ₆ D ₆ , TMS): δ 5.92 (s, 1H, H-3), 2.13
(t, 2H, J = 7.4 Hz), 1.95-1.90 (m, 4H), 1.52 (m, 2
H), 1.12 (m, 6H), 0.77-0.72 (m, 9H). ¹³ C-NMR (C ₆ D ₆ , TMS): δ 161.6, 160.9, 159.4, 11
4.7, 111.4, 32.8, 32.0, 30.7, 28.0, 24.1, 22.6, 21.
1, 14.1, 13.9, 13.8. IR (liquid film): 2964, 2936, 2876, 1729, 1632, 1545 cm
^-1 . GCMS (EI, 70 eV): m / z (relative intensity) 236 (M +, 21), 207
(11), 194 (24), 179 (40), 166 (100), 151 (56), 137
. (41), 71 (72 ) HR-MS (EI, 70 eV): Found 236.1795, calcd _{236.1775 (C 15 H 24 O 2} ) Elemental analysis C ₁₅ H ₂₄ O ₂ Found C, 76.30%; H, 10.31% Calculated C, 76.27%; H, 10.17%

Examples 2 to 10 The reaction was carried out in the same manner as in Example 1 except that the scale of the reaction in Example 1 was reduced to 40% and various catalysts were used in place of dichlorobis (triphenylphosphine) palladium. As a result of analysis by gas chromatography, the results shown in Table 1 were obtained.

[0023]

[Table 1]

Example 11 The reaction was carried out in the same manner as in Example 1 except that ethylbenzene was used instead of toluene and triethylamine was not added. As a result of analysis by gas chromatography, 4-butyl-5,6-diethyl-2H- Pyran-2-one is 27
% Yield.

Example 12 A reaction was carried out in the same manner as in Example 1 except that dimethylformamide was used instead of toluene, and analysis by gas chromatography revealed that 4-butyl-5,6-diethyl-2H
It was found that -pyran-2-one was formed in a yield of 42%.

Example 13 The reaction and separation and purification were carried out in the same manner as in Example 1 except that 3-hexyne was used instead of 4-octyne.
Butyl-5,6-diethyl-2H-pyran-2-one was obtained as a colorless oil in 72% isolated yield. This compound was a novel compound not described in any literature, and its physical properties and spectrum data were as follows.

Boiling point: 110 ° C./1.2 mmHg (Kugel roll). ¹ H-NMR (C ₆ D ₆ , TMS): δ 5.90 (s, 1H, H-3), 2.05-
1.79 (m, 6H), 1.10-0.67 (m, 13H). ¹³ C-NMR (C ₆ D ₆ , TMS): δ 161.8, 161.7, 159.3, 11
5.4, 111.5, 31.8, 32.6, 24.1, 22.6, 19.1, 15.0, 13.
9, 12.1.IR (liquid film): 2962, 2936, 2876, 1723, 1634, 1547 cm
^-1 . GCMS (EI, 70 eV): m / z (relative intensity) 208 (M +, 13), 166
(23), 138 (100), 123 (40), 109 (51), 57 (84). Elemental analysis C ₁₃ H ₂₀ O ₂ Found C, 75.10%; H, 9.74% Calculated C, 75.00% ; H, 9.62%

Example 14 The reaction and separation and purification were carried out in the same manner as in Example 1 except that 2-pentyne was used instead of 4-octyne.
Butyl-5-methyl-6-ethyl-2H-pyran-2-
On and 4-butyl-5-ethyl-6-methyl-2H
An approximately 1: 1 mixture of -pyran-2-one was obtained as a colorless oil in 67% isolated yield. These compounds are novel compounds which have not been published in any literature, and the physical properties and spectral data of the mixtures are as follows.

Boiling point: 105-110 ° C./1.5 mmHg (Kugelroll). ¹ H-NMR (C ₆ D ₆ , TMS): δ 5.88 (s, 1H, H-3), 2.05-
0.48 (m, 17H). ¹³ C-NMR (C ₆ D ₆ , TMS): δ 161.7, 161.6, 161.3, 15
9.7, 159.1, 157.4, 116.0, 111.4, 111.0, 109.1, 32.
7, 31.8, 30.6, 30.0, 24.6, 22.6, 22.5, 19.3, 16.7,
14.1, 13.9, 11.5, 11.1.IR (liquid film): 2962, 2936, 2876, 1717, 1634, 1549 cm
^-1 . GCMS (EI, 70 eV): m / z (relative intensity) 194 (M +, 10), 152
(11), 124 (100), 109 (40), 95 (25), 79 (16), 67 (2
4), 57 (34). Elemental analysis: C ₁₂ H ₁₈ O ₂ Found C, 73.95%; H, 9.44% Calculated C, 74.23%; H, 9.28%

Example 15 Reaction, separation and purification were carried out in the same manner as in Example 1 except that methyl (Z) -3-chloro-2-nonenoate was used instead of methyl (Z) -3-chloro-2-heptenoate. And purification by column chromatography was repeated using a mixed solvent of ethyl acetate and hexane (5:95). As a result, 4-hexyl-5,6-dipropyl-2H-pyran-2-one was converted to a colorless oil. As an isolated yield of 62%. This compound was a novel compound not described in any literature, and its physical properties and spectrum data were as follows.

Boiling point: 130 ° C./0.8 mmHg (Kugel roll). ¹ H-NMR (C ₆ D ₆ , TMS): δ 5.95 (s, 1H, H-3), 2.12
(t, 2H, J = 7.6 Hz), 1.95 (m, 4H), 1.50 (m, 2H), 1.
22-1.08 (m, 10H), 0.87 (t, 3H, J = 7.0 Hz), 0.75
(t, 3H, J = 7.3 Hz), 0.74 (t, 3H, J = 7.4 Hz). ¹³ C-NMR (C ₆ D ₆ , TMS): δ 161.6, 160.9, 159.3, 11
4.6, 111.5, 32.8, 32.3, 31.8, 29.3, 28.6, 28.1, 24.
1, 22.8, 21.1, 14.2, 14.1, 13.8.IR (liquid film): 2962, 2934, 2874, 1729, 1632, 1547 cm
^-1 . GCMS (EI, 70 eV): m / z (relative intensity) 264 (M +, 16), 235
(4), 207 (18), 194 (52), 179 (23), 166 (100), 151
(75), 137 (31), 123 (31), 71 (74). Elemental analysis C ₁₇ H ₂₈ O ₂ Found C, 77.00%; H, 10.85% Calculated C, 77.27%; H, 10.61%

Example 16 The procedure of Example 1 was repeated, except that methyl (Z) -6-cyano-3-chloro-2-hexenoate was used instead of methyl (Z) -3-chloro-2-heptenoate. Perform reaction and separation and purification, and further add ethyl acetate and hexane (15:85).
As a result of repeating purification by column chromatography using a mixed solvent of 4- (3-cyanopropyl)-
5,6-Dipropyl-2H-pyran-2-one was obtained as a colorless oil in 56% isolated yield. This compound was a novel compound not described in any literature, and its physical properties and spectrum data were as follows.

Boiling point: 125-130 ° C./1.0 mmHg (Kugelrohr). ¹ H-NMR (C ₆ D ₆ , TMS): δ 5.64 (s, 1H, H-3), 2.08
(t, 2H, J = 7.5 Hz), 1.79 (m, 4H), 1.49 (m, 2H), 1.
25 (t, 2H, J = 6.8 Hz), 1.11 (m, 2H), 0.89 (m, 2H),
0.77 (t, 3H, J = 7.3 Hz), 0.73 (t, 3H, J = 7.4 H
z). ¹³ C-NMR (C ₆ D ₆ , TMS): δ 161.4, 161.2, 156.9, 11
8.6, 114.3, 111.6, 32.8, 30.4, 27.9, 24.1, 23.8, 2
1.1, 16.1, 14.0, 13.8. IR (liquid film): 2960, 2932, 2876, 2248, 1721, 1630, 1545
cm ^-1 . GCMS (EI, 70 eV): m / z (relative intensity) 247 (M +, 20), 218
(30), 207 (17), 190 (100), 166 (22), 148 (19), 91
(22), 77 (31), 71 (60), 55 (20). Elemental analysis C ₁₅ H ₂₁ NO ₂ Found C, 72.39%; H, 8.66%; N, 5.72% Calculated C, 72.87% ; H, 8.50%; N, 5.67%

Example 17 Example 1 except that methyl (Z) -3-chlorocinnamate was used in place of methyl (Z) -3-chloro-2-heptenoate
The reaction and separation and purification were carried out in the same manner as described above, and the product was recrystallized from pentane and further purified. Rate obtained. This compound was a novel compound not described in any literature, and its physical properties and spectrum data were as follows.

Melting point: 96.0-97.5 ° C. ¹ H-NMR (CDCl ₃ , TMS): δ 7.42-7.22 (m, 5H), 6.03
(s, 1H, H-3), 2.54 (t, 2H, J = 7.6 Hz), 2.22 (t, 2
H, J = 7.8 Hz), 1.74 (m, 2H), 1.16 (m, 2H), 1.01
(t, 3H, J = 7.3 Hz), 0.69 (t, 3H, J = 7.2 Hz). ¹³ C-NMR (CDCl ₃ , TMS): δ 162.6, 162.1, 160.3, 13
7.6, 128.6, 128.4,127.4, 115.2, 112.9, 32.1, 28.6,
23.5, 21.2, 13.9, 13.8. IR (KBr): 2968, 2936, 2876, 1711, 1628, 1539, 1390,
940, 899, 768,706 cm ^-1 . GCMS (EI, 70 eV): m / z (relative intensity) 256 (M +, 23), 228
(32), 199 (100), 157 (28), 128 (20), 71 (50). Elemental analysis C ₁₇ H ₂₀ O ₂ Found C, 79.57%; H, 7.98% Calculated C, 79.69% ; H, 7.81%

Example 18 The procedure of Example 1 was repeated, except that methyl (Z) -3,6-dichloro-2-hexenoate was used instead of methyl (Z) -3-chloro-2-heptenoate. Separation and purification were performed, and purification by column chromatography was further repeated using a mixed solvent of ethyl acetate and hexane (5:95). As a result, 4- (3-chloropropyl) -5,6-
Dipropyl-2H-pyran-2-one was obtained as a colorless oil in 9% isolated yield. This compound was a novel compound not described in any literature, and its spectral data was as follows.

¹ H-NMR (C ₆ D ₆ , TMS): δ 5.77 (s, 1H,
H-3), 2.91 (t, 2H, J = 6.1 Hz), 2.08 (t, 2H, J = 7.
3 Hz), 1.96 (t, 2H, J = 7.7 Hz), 1.86 (t, 2H, J =
8.1 Hz), 1.54-1.06 (m, 6H), 0.74 (t, 3H, J = 7.3 H
z), 0.73 (t, 3H, J = 7.4 Hz). ¹³ C-NMR (C ₆ D ₆ , TMS): δ 161.4, 161.3, 157.7, 11
4.4, 111.7, 44.0, 32.8, 31.0, 29.1, 27.9, 24.1, 21.
1, 14.0, 13.8. IR (liquid film): 2966, 2936, 2876, 1725, 1632, 1545 cm
^-1 . GCMS (EI, 70 eV): m / z (relative intensity) 256 (M +, 18), 228
(15), 199 (89), 166 (100), 151 (26), 123 (20), 107
(13), 91 (37), 71 (82), 55 (57). Elemental analysis C ₁₄ H ₂₁ ClO ₂ Found C, 65.03%; H, 8.35% Calculated C, 65.50%; H, 8.19%

Example 19 The reaction was carried out in the same manner as in Example 1 except that 1-phenyl-1-butyne was used instead of 4-octyne, and analyzed by gas chromatography and GCMS.
It was found that ethyl-6-phenyl-2H-pyran-2-one and 4-butyl-5-phenyl-6-ethyl-2H-pyran-2-one were formed. Separation and purification were carried out in the same manner as in Example 1, and purification by column chromatography was repeated using a mixed solvent of ethyl acetate and hexane (5:95). As a result, the main product, 4-
Butyl-5-ethyl-6-phenyl-2H-pyran-2
The -one was obtained as a colorless oil in 10% isolated yield. This compound was a novel compound not described in any literature, and its spectral data was as follows.

¹ H-NMR (CDCl ₃ , TMS): δ 7.44-7.37 (m,
3H), 7.15-7.12 (m, 2H), 6.06 (s, 1H, H-3), 2.27-2.
07 (m, 4H), 1.34-1.08 (m, 7H), 0.74 (t, 3H, J = 7.2
Hz). ¹³ C-NMR (CDCl ₃ , TMS): δ 163.1, 163.0, 160.8, 13
4.4, 130.1, 128.7, 128.0, 118.8, 110.1, 33.2, 30.1,
25.3, 22.1, 13.8.IR (liquid film): 2962, 2934, 2874, 1727, 1632, 1545, 768,
704 cm ^-1 . GCMS (EI, 70 eV): m / z (relative intensity) 256 (M +, 13), 214
(30), 186 (100), 171 (23), 128 (24), 57 (68). Elemental analysis C ₁₇ H ₂₀ O ₂ Found C, 79.55%; H, 7.90% Calculated C, 79.69% ; H, 7.81%

Example 20 A reaction, separation and purification were carried out in the same manner as in Example 1 except that phenyltrimethylsilylacetylene was used instead of 4-octyne, and ethyl acetate and hexane (2: 9
As a result of repeating purification by column chromatography using the mixed solvent in 8), 4-butyl-5-trimethylsilyl-6-phenyl-2H-pyran-2-one was isolated as a colorless viscous oil at 11%. Obtained in yield. This compound was a novel compound not described in any literature, and its spectral data was as follows.

¹ H-NMR (C ₆ D ₆ , TMS): δ 7.02-7.00 (m,
3H), 6.86-6.83 (m, 2H), 6.09 (s, 1H, H-3), 1.74
(t, 2H, J = 7.6 Hz), 1.06-0.81 (m, 4H), 0.58 (t, 3
H, J = 7.2 Hz), -0.12 (s, 9H). ¹³ C-NMR (C ₆ D ₆ , TMS): δ 168.4, 164.1, 158.5, 13
4.5, 131.2, 131.0, 128.4, 128.3, 112.7, 32.7, 30.1,
22.1, 13.6, -1.46.IR (Liquid film): 2956, 2934, 2874, 1731, 1495, 1253, 864,
847 cm ^-1 . GCMS (EI, 70 eV): m / z (relative intensity) 300 (M +, 6), 285
(2), 271 (6), 258 (2), 243 (26), 230 (3), 211 (3),
181 (4), 171 (2), 141 (3), 128 (5), 115 (6), 91
. (4), 73 (100 ), 59 (3) HR-MS (EI, 70 eV): Found 300.1544, calcd _{300.1544 (C 18 H 24 O 2} Si)

Example 21 A reaction and separation and purification were carried out in the same manner as in Example 1 except that 2,7-dimethyl-1-octen-3-yne was used instead of 4-octyne, and ethyl acetate and hexane (2 : 98), and the purification by column chromatography was repeated using a mixed solvent of 4-butyl-5-isopropenyl-6-isopentyl-2H-pyran-2-.
On or 4-butyl-5-isopentyl-6-isopropenyl-2H-pyran-2-one was obtained as a colorless oil in 17% isolated yield. This compound was a novel compound not described in any literature, and its spectral data was as follows.

¹ H-NMR (C ₆ D ₆ , TMS): δ 5.98 (s, 1H,
H-3), 4.98-4.95 (m, 2H), 2.15-1.95 (m, 4H), 1.79
(s, 3H), 1.16-1.04 (m, 7H), 0.81-0.75 (m, 9H). ¹³ C-NMR (C ₆ D ₆ , TMS): δ 161.0, 159.6, 159.5, 13
8.1, 118.6, 115.1, 112.9, 40.5, 31.9, 30.9, 28.6, 2
4.8, 22.7, 22.4, 21.5, 13.9. IR (liquid film): 2960, 2932, 2874, 1734, 1543, 1075 cm
^-1 . GCMS (EI, 70 eV): m / z (relative intensity) 262 (M +, 10), 205
(14), 191 (24), 177 (27), 163 (34), 150 (28), 107
. (24), 91 (59 ), 79 (47), 69 (100), 55 (69) HR-MS (EI, 70 eV): Found 262.1925, calcd _{262.1931 (C 17 H 26 O 2} )

[0044]

According to the method of the present invention, 3-halogeno-2
-Various pyrones having a high utility value in organic synthesis can be efficiently and safely produced from an alkenoic acid ester, preferably a 3-chloro-2-alkenoic acid ester and an acetylene compound, and the separation and purification thereof are easy. . Also,
According to the present invention, novel pyrones are provided. Therefore,
The industrial significance of the present invention is enormous.

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (reference) // C07B 61/00 300 C07B 61/00 300 (72) Inventor Mizumo Hana 2-28-20 Umezono, Tsukuba, Ibaraki Prefecture −104 F term (reference) 4C062 DD20 DD22 4H039 CA42 CG20

Claims (6)

[Claims] 1. In the presence of a Group 10 metal-containing catalyst, a compound of the general formula (1) (Wherein, R ¹ and R ² represent the same or different monovalent hydrocarbon groups, and X represents a halogen atom.) A 3-halogeno-2-alkenoic acid ester represented by the general formula: (2) (Wherein, R ³ and R ⁴ represent a monovalent hydrocarbon group, a heteroaromatic ring group, or a silyl group), characterized by reacting with an acetylene compound represented by the following general formula (3): 3] (Wherein R ¹ , R ² , R ³ , and R ⁴ are the same as those in formulas (1) and (2)). 2. The 3-halogeno represented by the general formula (1)
The method according to claim 1, wherein the halogen atom of the 2-alkenoic acid ester is a chlorine atom. 3. The method according to claim 1, wherein the Group 10 metal of the Group 10 metal-containing catalyst is palladium. 4. The method according to claim 1, wherein the reaction is carried out in the presence of an organic base. 5. The method according to claim 4, wherein the organic base is a trialkylamine. 6. A compound of the general formula (3) (In the formula, R ¹ , R ³ and R ⁴ are the same as those in the formulas (1) and (2).) 4,5,6-Substituted alpha-pyrones represented by the formula: