JP2009029733A - METHOD FOR PRODUCING alpha,beta-UNSATURATED CARBONYL COMPOUND - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To produce an α,β-unsaturated carbonyl compound in high yield. <P>SOLUTION: The method for producing the α,β-unsaturated carbonyl compound comprises reacting propargyl alcohol with carbon dioxide in a polar solvent in the presence of a transition metal catalyst and a base, to convert them into the corresponding α,β-unsaturated carbonyl compound efficiently. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a novel process for producing an α, β-unsaturated carbonyl compound.

A method for synthesizing α, β-unsaturated carbonyl compounds from propargyl alcohol is conventionally known as the Meyer-Schuster reaction, which involves two reaction steps:
(1) activating and releasing the hydroxyl group of propargyl alcohol to form a cationic intermediate;
(2) It comprises a step of adding an oxygen acid oxidant to this intermediate to produce an α, β-unsaturated carbonyl compound via the allene-enolate intermediate (see, for example, Non-Patent Document 1). .

  In order to perform step (1), for example, a method in which a protonic acid is allowed to act is known. However, this method has a problem in that an intermediate carbocation intermediate undergoes a side reaction (Rupe rearrangement) to generate an α, β-unsaturated carbonyl compound having another structure (see, for example, Non-Patent Document 2). ).

  Therefore, an investigation was made to carry out the process up to step (2) as an intramolecular rearrangement reaction without generating a carbocation in the middle. For this purpose, a strategy has been adopted in which an oxometal reactant is used to activate a hydroxyl group as an ester of a metal acid and perform a nucleophilic attack with one oxygen atom. For example, certain results have been obtained using oxides such as vanadium, titanium, and molybdenum (see, for example, Non-Patent Documents 3 and 4).

However, this method has been pointed out as a problem:
i) The applicable substrate group is limited to tertiary propargyl alcohol,
ii) the acetylene moiety is limited to terminal acetylene, and
iii) The reaction temperature generally requires high temperature conditions.

For this reason, the use of rhenium oxide as a reactant was studied with the aim of realizing a wide range of applications and mild reaction conditions. This method has been reported to be applicable to other internal alkynes other than terminal alkynes under reaction conditions of about room temperature (see, for example, Non-Patent Document 5).
However, the following points are still raised as problems.
i) A large amount of catalyst,
ii) By-products due to the Rupe rearrangement can be seen,
iii) The phenylacetylene derivative has a low yield,
iv) The yield is not sufficient with secondary propargyl alcohol, and v) there is no reaction with primary propargyl alcohol.

Recently, the efficiency of this reaction has been improved from another viewpoint. That is, it is a study to increase the overall reaction efficiency by effectively activating the acetylene moiety in step (2). Since noble metal catalysts such as gold and ruthenium are known to effectively activate π bonds such as acetylene, research utilizing this has been reported. These methods can lower the reaction temperature depending on the substrate, but cannot be said to be a complete synthesis method because an expensive noble metal catalyst is used (see, for example, Non-Patent Documents 6 and 7).
Meyer, KH; Schuster, K. Chem. Ber. 1922, 55, 819-823. Smith, MB; March, J. March's Advanced Organic Chemistry, 5th ed; John Wiley &Sons; New York, 2001; p 423. Lorber, CY; Osborn, JA Tetrahedron Lett. 1996, 37, 853-856. Titanium alkoxide: Chabardes, P. Tetrahedron Lett. 1988, 29, 6253-6256. Under mild reaction conditions using a rhenium salt: Narasaka, K .; Kusama, H .; Hayashi, Y. Chem. Lett. 1991, 1413-1416. Cadierno, V .; Garcia-Garrido, SE; Gimeno, J. Adv. Synth. Catal. 2006, 348, 101-110. Lopez, SS; Engel, DA; Dudley, GB Synlett 2007, 6, 949-953.

  An object of the present invention is to provide a novel method for producing an α, β-unsaturated carbonyl compound with high yield, which solves the above-mentioned problems in the prior art.

  As a result of intensive studies to solve the above problems, the present inventors have made high yields of the corresponding α, β-unsaturated carbonyl compounds by reacting various propargyl alcohols with carbon dioxide in polar solvents. It has been found that it can be obtained at a rate, and the present invention has been completed.

（式中、
Ｒ¹およびＲ²は、同一または異なって、水素原子または有機基であり、
Ｒ³は、直接または酸素を介して結合する、水素原子または有機基である）
で表されるプロパルギルアルコールと二酸化炭素を、極性溶媒中、遷移金属触媒および塩基の存在下で反応させることによる、式（２）：

（式中、Ｒ¹、Ｒ²およびＲ³は上記と同義である）
で表されるα,β−不飽和カルボニル化合物の製造方法。 That is, the present invention is as follows:
1. Formula (1)

(Where
R ¹ and R ² are the same or different and are a hydrogen atom or an organic group,
R ³ is a hydrogen atom or an organic group bonded directly or via oxygen)
By reacting propargyl alcohol represented by the following formula with carbon dioxide in a polar solvent in the presence of a transition metal catalyst and a base:

(Wherein R ¹ , R ² and R ³ are as defined above)
The manufacturing method of the (alpha), (beta)-unsaturated carbonyl compound represented by these.

｛式中、
Ｒ¹およびＲ²は、同一または異なって、水素原子、Ｃ_1-6アルキル基［該Ｃ_1-6アルキル基は、無置換であるか、またはＣ_6-12アリール基（該Ｃ_6-12アリール基は、無置換であるか、またはＣ_1-6アルキル基、Ｃ_1-6アルコキシ基、ハロゲン原子、もしくは保護された水酸基で置換されている）、Ｃ_1-6アルコキシ基、ハロゲン原子、もしくは保護された水酸基で置換されている］、またはＣ_6-12アリール基（該Ｃ_6-12アリール基は、無置換であるか、またはＣ_1-6アルキル基、Ｃ_1-6アルコキシ基、ハロゲン原子、もしくは保護された水酸基で置換されている）であるか、または
Ｒ¹とＲ²が互いに結合してＣ_3-8シクロアルキルであり、
Ｒ³は、水素原子、ヒドロキシル基、Ｃ_1-6アルキル基［該Ｃ_1-6アルキル基は、無置換であるか、またはＣ_6-12アリール基（該Ｃ_6-12アリール基は、無置換であるか、またはＣ_1-6アルキル基、Ｃ_1-6アルコキシ基、ハロゲン原子、もしくは保護された水酸基で置換されている）、Ｃ_1-6アルコキシ基、ハロゲン原子、もしくは保護された水酸基で置換され
ている］、Ｃ_6-12アリール基（該Ｃ_6-12アリール基は、無置換であるか、またはＣ_1-6アルキル基、Ｃ_1-6アルコキシ基、ハロゲン原子、もしくは保護された水酸基で置換されている）、Ｃ_1-6アルコキシ基（該Ｃ_1-6アルコキシ基は、無置換であるか、またはＣ_1-6アルキル基、Ｃ_1-6アルコキシ基、ハロゲン原子、もしくは保護された水酸基で置換されている）、またはＣ_6-12アリールオキシ基（該Ｃ_6-12アリールオキシ基は、無置換であるか、またはＣ_1-6アルキル基、Ｃ_1-6アルコキシ基、ハロゲン原子、もしくは保護された水酸基で置換されている）である｝
で表されるプロパルギルアルコールと二酸化炭素を、極性溶媒中、遷移金属触媒および塩基の存在下で反応させることによる、式（２）：

（式中、Ｒ¹、Ｒ²およびＲ³は上記と同義である）
で表されるα,β−不飽和カルボニル化合物の製造方法。 2. Formula (1)

{Where,
R ¹ and R ² are the same or different and each represents a hydrogen atom, a C _1-6 alkyl group [the C _1-6 alkyl group is unsubstituted or a C _6-12 aryl group (the C _6-12 The aryl group is unsubstituted or substituted with a C _1-6 alkyl group, a C _1-6 alkoxy group, a halogen atom, or a protected hydroxyl group), a C _1-6 alkoxy group, a halogen atom, Or substituted with a protected hydroxyl group], or a C _6-12 aryl group (the C _6-12 aryl group is unsubstituted or a C _1-6 alkyl group, a C _1-6 alkoxy group, Substituted with a halogen atom or a protected hydroxyl group), or R ¹ and R ² are bonded to each other to form C _3-8 cycloalkyl,
R ³ represents a hydrogen atom, a hydroxyl group, a C _1-6 alkyl group [the C _1-6 alkyl group is unsubstituted or a C _6-12 aryl group (the C _6-12 aryl group is Substituted or substituted with a C _1-6 alkyl group, a C _1-6 alkoxy group, a halogen atom, or a protected hydroxyl group), a C _1-6 alkoxy group, a halogen atom, or a protected hydroxyl group Substituted with a C _6-12 aryl group (the C _6-12 aryl group is unsubstituted or a C _1-6 alkyl group, a C _1-6 alkoxy group, a halogen atom, or a protected group). Substituted with a hydroxyl group), a C _1-6 alkoxy group (the C _1-6 alkoxy group is unsubstituted, a C _1-6 alkyl group, a C _1-6 alkoxy group, a halogen atom, or is substituted with a protected hydroxyl group), or C _6-12 aryloxy group (the _6-12 aryloxy group is unsubstituted or substituted by C _1-6 alkyl, C _1-6 alkoxy group is substituted with a halogen atom or a protected hydroxyl group)}
By reacting propargyl alcohol represented by the following formula with carbon dioxide in a polar solvent in the presence of a transition metal catalyst and a base:

(Wherein R ¹ , R ² and R ³ are as defined above)
The manufacturing method of the (alpha), (beta)-unsaturated carbonyl compound represented by these.

3. R ¹ and R ² are the same or different and are a C _1-6 alkyl group, or R ¹ and R ² are bonded to each other and are C _3-8 cycloalkyl,
Above 1. Or 2. The manufacturing method as described.

4). R ¹ and R ² are the same or different and are an unsubstituted C _1-6 alkyl group, or R ¹ and R ² are bonded to each other and are C _3-8 cycloalkyl,
Above 1. ~ 3. The manufacturing method in any one of.

5). 1. R ³ is a hydrogen atom, a C _1-6 alkyl group, or a C _1-6 alkoxy group. ~ 4. The manufacturing method in any one of.

6). R ³ is a hydrogen atom, a C _1-6 alkyl group [the C _1-6 alkyl group is unsubstituted, or a phenyl group (the phenyl group is unsubstituted, or C _1-6 alkyl Or a C _1-6 alkoxy group, substituted with a C _1-6 alkoxy group, a halogen atom or a protected hydroxyl group), or an unsubstituted C _1-6 alkoxy group. ~ 5. The manufacturing method in any one of.

7). R ³ is a hydrogen atom, a C _1-6 alkyl group (the C _1-6 alkyl group is unsubstituted or substituted with an unsubstituted phenyl group), or an unsubstituted C _1-6 The above 1. which is an alkoxy group. ~ 6. The manufacturing method in any one of.

8). R ¹ and R ² are the same or different and are an unsubstituted C _1-6 alkyl group, or R ¹ and R ² are bonded to each other to be C _3-8 cycloalkyl,
R ³ is a hydrogen atom, a C _1-6 alkyl group (the C _1-6 alkyl group is unsubstituted or substituted with an unsubstituted phenyl group), or an unsubstituted C _1-6 The above 1. which is an alkoxy group. ~ 7. The manufacturing method in any one of.

9. 1. The polar solvent used is selected from the group consisting of formamide, dimethylformamide, dimethylacetamide, dichloromethane, and benzene chloride. ~ 8. The manufacturing method in any one of.

10. 8. The polar solvent used is formamide, dimethylformamide, or dimethylacetamide. The manufacturing method as described in.

11. Catalysts used are silver methanesulfonate (I), gold (I) chloride, gold (III) chloride, sodium tetrachloroaurate (III) dihydrate, gold chlorotriphenylphosphine, tris (acetylacetonato) rhodium ( III), mercury triflate (II), platinum chloride (II), palladium chloride (II), palladium acetate (II), copper chloride (I), silver perchlorate (I), silver cyanide (I), trifluoromethane Silver sulfonate (I), silver carbonate (I), silver tetrafluoroborate (I), silver fluoride (I), silver hexafluorophosphate (I), silver hexafluoroantimonate (I), silver acetate ( I) above, selected from the group consisting of p-toluenesulfone silver (I). -10. The manufacturing method in any one of.

12 The above 11. wherein the catalyst used is silver (I) methanesulfonate or gold (III) chloride. The manufacturing method as described in.

13. 1. The above 1, wherein the base used is diisopropylethylamine, diazabicycloundecene, or 1,5-diazabicyclo [4,3,0] -5-nonene. -12. The manufacturing method in any one of.

14 1. The reaction temperature is from room temperature to 60 ° C. ~ 13. The manufacturing method in any one of.

15. 1. The carbon dioxide pressure is from 0.1 MPa to 2 MPa. -14. The manufacturing method in any one of.

16. Above 1. -15. Or a compound selected from the group consisting of the following:
5-methyl-1-phenyl-4-hexen-3-one;
5-ethyl-1-phenyl-4-hepten-3-one;
5-isopropyl-6-methyl-1-phenyl-4-hepten-3-one;
1-cyclopentylidene-4-phenyl-2-butanone;
1-cyclohexylidene-4-phenyl-2-butanone;
1-cycloheptylidene-4-phenyl-2-butanone;
1,5-diphenyl-4-hexen-3-one;
1,1-diphenyl-1-hexen-3-one;
1-phenyl-4-hexen-3-one;
1-phenyl-4-hepten-3-one;
1-phenyl-4-penten-3-one;
2-methyl-2-decen-4-one;
Ethyl 3-methyl-5-phenylpent-2-enoate; and ethyl 5-phenylpent-2-enoate.

  The method of the present invention is based on a novel reaction. According to the method of the present invention, an α, β-unsaturated carbonyl compound can be produced in a high yield under a reaction condition much milder than that of the conventional method, and the range of applicable substrates is wide. It greatly expands and various carbonyl compounds can be produced. Moreover, non-toxic carbon dioxide gas that is inexpensive and easy to handle, and a transition metal catalyst, particularly a silver catalyst that is inexpensive and highly stable can be used as the metal catalyst.

すなわち、本発明の反応では、まずプロパルギルアルコールと二酸化炭素が反応して、カーボネート中間体が生成し、次にそのβ−炭素がアタックされて、［３,３］−シグマトロピー転位が進み、α,β−不飽和カルボニル化合物が生成するものと考えられる。 Hereinafter, the present invention will be described in detail.
The present invention is believed to be due to the reaction mechanism shown by the following scheme.

That is, in the reaction of the present invention, first, propargyl alcohol and carbon dioxide react to produce a carbonate intermediate, then the β-carbon is attacked, and the [3,3] -sigmatropic rearrangement proceeds, α, It is considered that a β-unsaturated carbonyl compound is formed.

The above reaction mechanism is supported by isotope experiments using C ¹⁸ O ₂ . According to this isotope experiment, MW. 188 α, β-unsaturated ketone was obtained, but when C ¹⁸ O ₂ was used, MW. 190 α, β-unsaturated ketone was obtained, and the reaction under a nitrogen atmosphere did not proceed at all. These results suggest that the reaction mechanism in the present invention is promoted by carbon dioxide, and the reaction proceeds not by intermolecular addition of water or carbonate anions but by [3,3] -sigmatropic rearrangement within the molecule. .

  In the present invention, “n” is normal, “i” is iso, “s” is secondary, “t” or “tert” is tertiary, “c” is cyclo, and “m” is meta. , “P” means para, “Ms” means methanesulfonyl group, “Ac” means acetyl group, “Ph” means phenyl group, “Et” means ethyl group, “rt” means room temperature.

（式中、
Ｒ¹およびＲ²は、同一または異なって、水素原子または有機基であり、
Ｒ³は、直接または酸素を介して結合する、水素原子または有機基である）
で表されるプロパルギルアルコールである。 The reaction of the present invention is applicable to a wide range of substrates, that is, propargyl alcohol used as a raw material in the present invention is represented by the formula (1)

(Where
R ¹ and R ² are the same or different and are a hydrogen atom or an organic group,
R ³ is a hydrogen atom or an organic group bonded directly or via oxygen)
It is propargyl alcohol represented by.

で表されるプロパルギルアルコールであって、式中、
Ｒ¹およびＲ²は、同一または異なって、水素原子、Ｃ_1-6アルキル基［該Ｃ_1-6アルキル基は、無置換であるか、またはＣ_6-12アリール基（該Ｃ_6-12アリール基は、無置換であるか、またはＣ_1-6アルキル基、Ｃ_1-6アルコキシ基、ハロゲン原子、もしくは保護された水酸基で置換されている）、Ｃ_1-6アルコキシ基、ハロゲン原子、もしくは保護された水酸基で置換されている］、またはＣ_6-12アリール基（該Ｃ_6-12アリール基は、無置換であるか、またはＣ_1-6アルキル基、Ｃ_1-6アルコキシ基、ハロゲン原子、もしくは保護された水酸基で置換されている）であるか、または
Ｒ¹とＲ²が互いに結合して３〜８員環であり、
Ｒ³は、水素原子、ヒドロキシル基、Ｃ_1-6アルキル基［該Ｃ_1-6アルキル基は、無置換であるか、またはＣ_6-12アリール基（該Ｃ_6-12アリール基は、無置換であるか、またはＣ_1-6アルキル基、Ｃ_1-6アルコキシ基、ハロゲン原子、もしくは保護された水酸基で置換されている）、Ｃ_1-6アルコキシ基、ハロゲン原子、もしくは保護された水酸基で置換され
ている］、Ｃ_6-12アリール基（該Ｃ_6-12アリール基は、無置換であるか、またはＣ_1-6アルキル基、Ｃ_1-6アルコキシ基、ハロゲン原子、もしくは保護された水酸基で置換されている）、Ｃ_1-6アルコキシ基（該Ｃ_1-6アルコキシ基は、無置換であるか、またはＣ_1-6アルキル基、Ｃ_1-6アルコキシ基、ハロゲン原子、もしくは保護された水酸基で置換されている）、またはＣ_6-12アリールオキシ基（該Ｃ_6-12アリールオキシ基は、無置換であるか、またはＣ_1-6アルキル基、Ｃ_1-6アルコキシ基、ハロゲン原子、もしくは保護された水酸基で置換されている）である。 More specifically, the formula (1)

Propargyl alcohol represented by the formula:
R ¹ and R ² are the same or different and each represents a hydrogen atom, a C _1-6 alkyl group [the C _1-6 alkyl group is unsubstituted or a C _6-12 aryl group (the C _6-12 The aryl group is unsubstituted or substituted with a C _1-6 alkyl group, a C _1-6 alkoxy group, a halogen atom, or a protected hydroxyl group), a C _1-6 alkoxy group, a halogen atom, Or substituted with a protected hydroxyl group], or a C _6-12 aryl group (the C _6-12 aryl group is unsubstituted or a C _1-6 alkyl group, a C _1-6 alkoxy group, Are substituted with a halogen atom or a protected hydroxyl group), or R ¹ and R ² are bonded to each other to form a 3- to 8-membered ring,
R ³ represents a hydrogen atom, a hydroxyl group, a C _1-6 alkyl group [the C _1-6 alkyl group is unsubstituted or a C _6-12 aryl group (the C _6-12 aryl group is Substituted or substituted with a C _1-6 alkyl group, a C _1-6 alkoxy group, a halogen atom, or a protected hydroxyl group), a C _1-6 alkoxy group, a halogen atom, or a protected hydroxyl group Substituted with a C _6-12 aryl group (the C _6-12 aryl group is unsubstituted or a C _1-6 alkyl group, a C _1-6 alkoxy group, a halogen atom, or a protected group). Substituted with a hydroxyl group), a C _1-6 alkoxy group (the C _1-6 alkoxy group is unsubstituted, a C _1-6 alkyl group, a C _1-6 alkoxy group, a halogen atom, or is substituted with a protected hydroxyl group), or C _6-12 aryloxy group (the _6-12 aryloxy group is unsubstituted or substituted by C _1-6 alkyl, C _1-6 alkoxy group is substituted with a halogen atom or a protected hydroxyl group).

The C _1-6 alkyl group in R ¹ , R ² , R ³ is a linear, branched or cyclic alkyl group having 1 to 6 carbon atoms, such as methyl, ethyl, n-propyl, i- Propyl, c-propyl, n-butyl, i-butyl, s-butyl, t-butyl, c-butyl, 1-methyl-c-propyl, 2-methyl-c-propyl, n-pentyl, 1-methyl- n-butyl, 2-methyl-n-butyl, 3-methyl-n-butyl, 1,1-dimethyl-n-propyl, 1,2-dimethyl-n-propyl, 2,2-dimethyl-n-propyl, 1-ethyl-n-propyl, c-pentyl, 1-methyl-c-butyl, 2-methyl-c-butyl, 3-methyl-c-butyl, 1,2-dimethyl-c-propyl, 2,3- Dimethyl-c-propyl, 1-ethyl-c-propyl, 2-ethyl -C-propyl, n-hexyl, 1-methyl-n-pentyl, 2-methyl-n-pentyl, 3-methyl-n-pentyl, 4-methyl-n-pentyl, 1,1-dimethyl-n-butyl 1,2-dimethyl-n-butyl, 1,3-dimethyl-n-butyl, 2,2-dimethyl-n-butyl, 2,3-dimethyl-n-butyl, 3,3-dimethyl-n-butyl 1-ethyl-n-butyl, 2-ethyl-n-butyl, 1,1,2-trimethyl-n-propyl, 1,2,2-trimethyl-n-propyl, 1-ethyl-1-methyl-n -Propyl, 1-ethyl-2-methyl-n-propyl, c-hexyl, 1-methyl-c-pentyl, 2-methyl-c-pentyl, 3-methyl-c-pentyl, 1-ethyl-c-butyl 2-ethyl-c-butyl, 3-ethyl-c-butyl, 1,2-dimethyl-c-butyl, 1,3-dimethyl-c-butyl, 2,2-dimethyl-c-butyl, 2,3-dimethyl-c-butyl, 2,4-dimethyl-c-butyl, 3, , 3-dimethyl-c-butyl, 1-n-propyl-c-propyl, 2-n-propyl-c-propyl, 1-i-propyl-c-propyl, 2-i-propyl-c-propyl, 1 2,2-trimethyl-c-propyl, 1,2,3-trimethyl-c-propyl, 2,2,3-trimethyl-c-propyl, 1-ethyl-2-methyl-c-propyl, 2-ethyl Groups such as -1-methyl-c-propyl, 2-ethyl-2-methyl-c-propyl and 2-ethyl-3-methyl-c-propyl are typical. Preferred alkyl groups in the present invention are C _1-3 alkyl groups, more preferably methyl groups and ethyl groups.

R ¹ and R ² may be bonded to each other to form a 3- to 8-membered ring. Examples of such a ring structure include a cyclopentane ring, a cyclohexane ring, a pyrrolidine ring, and a piperidine ring. These rings may have a substituent, and examples of the substituent include the same groups as those described above, such as a hydroxyl group, an alkoxy group, an aryloxy group, a halogen atom, a cyano group, a nitro group, and a sulfonyl group. It is done. A preferred ring structure formed by R ¹ and R ² in the present invention is C _3-8 cycloalkyl, and specific examples include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, and cyclooctyl. A more preferred structure is C _5-6 cycloalkyl, specifically, cyclopentyl or cyclohexyl.

The C _6-12 aryl group in R ¹ , R ² , and R ³ is an aromatic group having 6 to 12 carbon atoms, such as a substituted or unsubstituted group such as a phenyl group, an indenyl group, a naphthyl group, and a tetrahydronaphthyl group. Aromatic groups are typical. A preferable C _6-12 aryl group in the present invention includes a phenyl group.

The C _1-6 alkoxy group in R ¹ , R ² , R ³ is a linear, branched or cyclic alkoxy group having 1 to 6 carbon atoms, and includes methoxy, ethoxy, n-propoxy, i-propoxy, c-propoxy, n-butoxy, i-butoxy, s-butoxy, t-butoxy, c-butoxy, 1-methyl-c-propoxy, 2-methyl-c-propoxy, n-pentyloxy, 1-methyl-n -Butoxy, 2-methyl-n-butoxy, 3-methyl-n-butoxy, 1,1-dimethyl-n-propoxy, 1,2-dimethyl-n-propoxy, 2,2-dimethyl-n-propoxy, 1 -Ethyl-n-propoxy, c-pentyloxy, 1-methyl-c-butoxy, 2-methyl-c-butoxy, 3-methyl-c-butoxy, 1,2-dimethyl-c-propoxy, 2,3- Jime Ru-c-propoxy, 1-ethyl-c-propoxy, 2-ethyl-c-propoxy, n-hexyloxy, 1-methyl-n-pentyloxy, 2-methyl-n-pentyloxy, 3-methyl-n -Pentyloxy, 4-methyl-n-pentyloxy, 1,1-dimethyl-n-butoxy, 1,2-dimethyl-n-butoxy, 1,3-dimethyl-n-butoxy, 2,2-dimethyl-n -Butoxy, 2,3-dimethyl-n-butoxy, 3,3-dimethyl-n-butoxy, 1-ethyl-n-butoxy, 2-ethyl-n-butoxy, 1,1,2-trimethyl-n-propoxy 1,2,2-trimethyl-n-propoxy, 1-ethyl-1-methyl-n-propoxy, 1-ethyl-2-methyl-n-propoxy, c-hexyloxy, 1-methyl-c-pentyloxy 2-methyl-c-pentyloxy, 3-methyl-c-pentyloxy, 1-ethyl-c-butoxy, 2-ethyl-c-butoxy, 3-ethyl-c-butoxy, 1,2-dimethyl-c- Butoxy, 1,3-dimethyl-c-butoxy, 2,2-dimethyl-c-butoxy, 2,3-dimethyl-c-butoxy, 2,4-dimethyl-c-butoxy, 3,3-dimethyl-c- Butoxy, 1-n-propyl-c-propoxy, 2-n-propyl-c-propoxy, 1-i-propyl-c-propoxy, 2-i-propyl-c-propoxy, 1,2,2-trimethyl- c-propoxy, 1,2,3-trimethyl-c-propoxy, 2,2,3-trimethyl-c-propoxy, 1-ethyl-2-methyl-c-propoxy, 2-ethyl-1-methyl-c- Propoxy, 2-ethyl- And groups such as 2-methyl-c-propoxy and 2-ethyl-3-methyl-c-propoxy. A preferred alkoxy group in the present invention is a C _1-3 alkoxy group, and more preferably a methoxy group.

Examples of the protecting group for R ¹ , R ² and R ³ include a C _1-4 alkoxymethyl group [for example, MOM (methoxymethyl) group, MEM (2-methoxyethoxymethyl) group, ethoxymethyl group, n-propoxymethyl group, Examples include i-propoxymethyl group, n-butoxymethyl group, iBM (isobutyloxymethyl) group, BUM (t-butoxymethyl) group, POM (pivaloyloxymethyl) group and SEM (trimethylsilylethoxymethyl) group. Preferably MOM (methoxymethyl) group, MEM (2-methoxyethoxymethyl) group, POM (pivaloyloxymethyl) group and the like], aryloxymethyl group [for example, BOM (benzyloxymethyl) group, PMBM (P-methoxybenzyloxymethyl) group and p-AOM (p-anisyloxy) Chill) group and the like, with preference given to a benzyl oxymethyl group], C _1-4 alkyl aminomethyl group (e.g. dimethylaminomethyl group, etc.), a substituted acetamidomethyl group [e.g. Acm (acetamidomethyl) group And Tacm (trimethylacetamidomethyl) group and the like], substituted thiomethyl groups [for example, MTM (methylthiomethyl) group, PTM (phenylthiomethyl) group, Btm (benzylthiomethyl) group and the like), carboxyl Group, C _1-7 acyl group [for example, formyl group, acetyl group, fluoroacetyl group, difluoroacetyl group, trifluoroacetyl group, chloroacetyl group, dichloroacetyl group, trichloroacetyl group, propionyl group, Pv (pivaloyl) group and A tigloyl group, etc.], ants Carbonyl group (for example, benzoyl group, p-bromobenzoyl group, p-nitrobenzoyl group, 2,4-dinitrobenzoyl group, benzoylformyl group, benzoylpropionyl group, 3-phenylpropionyl group, etc.), C _1-4 alkoxy Carbonyl group [for example, methoxycarbonyl group, ethoxycarbonyl group, n-propoxycarbonyl group, i-propoxycarbonyl group, n-butoxycarbonyl group, i-butoxycarbonyl group, BOC (t-butoxycarbonyl) group, AOC (t-amyl) Oxycarbonyl) group, VOC (vinyloxycarbonyl) group, AOC (allyloxycarbonyl) group, Teoc (2- (trimethylsilyl) ethoxycarbonyl) group, Troc (2,2,2-trichloroethoxycarbonyl) group, etc. Preferred And a BOC group and the like], an aryloxycarbonyl group [for example, a Z (benzyloxycarbonyl) group, a p-nitrobenzyloxycarbonyl group, a MOZ (p-methoxybenzyloxycarbonyl) group and the like], C _{1 -4} alkylaminocarbonyl group [for example, methylcarbamoyl group, Ec (ethylcarbamoyl) group, n-propylcarbamoyl group, etc.], arylaminocarbonyl group (for example, phenylcarbamoyl group etc.), trialkylsilyl group [ For example, TMS (trimethylsilyl) group, TES (triethylsilyl) group, TIPS (triisopropylsilyl) group, DEIPS (diethylisopropylsilyl) group, DMIPS (dimethylisopropylsilyl) group, DTBMS (di-t-butylmethylsilyl) Group, IPDMS (isopropyldimethylsilyl) group, TBDMS (t-butyldimethylsilyl) group, TDS (texyldimethylsilyl) group and the like, preferably TBDMS (t-butyldimethylsilyl) group and the like], Trialkylarylsilyl group [for example, DPMS (diphenylmethylsilyl) group, TBDPS (t-butyldiphenylsilyl) group, TBMPS (t-butyldimethoxyphenylsilyl) group, TPS (triphenylsilyl) group, dimethylphenylsilyl, etc. Alkylsulfonyl group [for example, Ms (methanesulfonyl) group, ethanesulfonyl group, benzylsulfonyl group, etc.] and arylsulfonyl group [for example, benzenesulfonyl group, Ts (p-toluenesulfonyl) group, p-chlorobenze Sulfonyl group, MBS (p-methoxybenzenesulfonyl) group, m-nitrobenzenesulfonyl group, iMds (2,6-dimethoxy-4-methylbenzenesulfonyl) group, Mds (2,6-dimethyl-4-methoxybenzenesulfonyl) group Mtb (2,4,6-trimethoxybenzenesulfonyl) group, Mte (2,3,5,6-tetramethyl-4-methoxybenzenesulfonyl) group, Mtr (2,3,6-trimethyl-4-methoxy) Benzenesulfonyl) group, Mts (2,4,6-trimethylbenzenesulfonyl) group, Pme (pentamethylbenzenesulfonyl) group and the like]. In addition, 1-methyl-1-methoxyethyl group, 1-ethoxyethyl group, 2,2,2-trichloroethyl group, 2-trimethylsilylethoxy group, t-butyl group, allyl group, benzyl group, p- Examples include methoxybenzyl group, 2,4-dinitrophenyl group, p-chlorophenyl group, p-methoxyphenyl group, tetrahydropyranyl group, tetrahydrofuranyl group and the like. Preferable protecting groups include a trialkylsilyl group, a trialkylarylsilyl group or a tetrahydropyranyl group, and more preferably a dimethylphenylsilyl or tetrahydropyranyl group.
A halogen atom is a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom.

  The polar solvent used in the present invention is not particularly limited as long as it does not react with the propargyl alcohol, carbon dioxide and base used. For example, formamide, dimethylformamide (DMF), dimethylacetamide (DMA), dichloromethane, chloride Examples include methyl and benzene chloride. Preferred are DMF, DMA and formamide, and more preferred is formamide. These may be used alone or in combination of two or more. As a usage-amount of a polar solvent, it can add in the range of 0.5-100, Preferably it is 10-100, More preferably, it is 50-100 with respect to the propargyl alcohol which is a raw material.

Transition metal catalysts used in the present invention include transition metals, salts and complexes thereof. Examples of the transition metal include, but are not limited to, silver, gold, copper, palladium, platinum, mercury, rhodium, and the like. Specific examples of the catalyst include silver methanesulfonate (I) (AgOMs), gold chloride (I), gold chloride (III), sodium tetrachloroaurate (III) dihydrate (NaAuCl ₄ (2H ₂ O)). ), Chlorotriphenylphosphine gold ((Ph ₃ P) AuCl), tris (acetylacetonato) rhodium (III), mercury triflate (II), platinum chloride (II), palladium chloride (II), palladium acetate (II) , Copper chloride (I), silver perchlorate (I), silver cyanide (I), silver trifluoromethanesulfonate (I), silver carbonate (I), silver tetrafluoroborate (I), silver fluoride ( I), silver hexafluorophosphate (I), silver hexafluoroantimonate (I), silver acetate (I), silver p-toluenesulfone (I) and the like. Preferred catalysts are AgOMs, gold (I) chloride, gold (III) chloride, NaAuCl ₄ (2H ₂ O), (Ph ₃ P) AuCl, and particularly preferred catalysts are AgOMs and gold (III) chloride. The amount of transition metal catalyst used is usually from 0.01 to 100 mol%, preferably from 0.1 to 20 mol%, more preferably from 0.5 to 10 mol%, based on 1 mol of the compound of formula (I). It is.

Examples of the base used in the present invention include methylamine, dimethylamine, ethylamine, ethylmethylamine, diethylamine, trimethylamine, ethyldimethylamine, diethylmethylamine, triethylamine, tri-n-butylamine, diisopropylethylamine (i-Pr _2). NEt), N-methylpyrrolidine, N-ethylpyrrolidine, N-methylpiperidine, N-ethylpiperidine and other alkylamines, N-trimethylsilyldimethylamine, N-triethylsilyldimethylamine, N-tert-butylmethylsilyldimethylamine N-trimethylsilyldiethylamine, N-triethylsilyldiethylamine, N-tert-butyldimethylsilyldiethylamine, N-trimethylsilyl-n-propylamine Alkyl such as N-triethylsilyldi-n-propylamine, N-tert-butyldimethylsilyldi-n-propylamine, N-trimethylsilyldiisopropylamine, N-triethylsilyldiisopropylamine, N-tert-butyldimethylsilyldiisopropylamine Alkylamine-N-oxides such as silylamines, trimethylamine-N-oxide, triethylamine-N-oxide, tri-n-propylamine-N-oxide, triisopropylamine-N-oxide, aniline, N-methylaniline N-ethylaniline, Nn-propylaniline, N-isopropylaniline, dimethylphenylamine, ethylmethylphenylamine, diethylphenylamine, diphenylamine, diphenylmethylamine, Arylamines such as phenylethylamine, n-propyldiphenylamine, isopropyldiphenylamine, triphenylamine, arylsilylamines such as N-trimethylsilyldiphenylamine, N-triethylsilyldiphenylamine, N-tert-butyldimethylsilyldiphenylamine, dimethylphenylamine- N-oxide, ethylmethylphenylamine-N-oxide, diethylphenylamine-N-oxide, diphenylmethylamine-N-oxide, diphenylethylamine-N-oxide, n-propyldiphenylamine-N-oxide, isopropyldiphenylamine-N- Oxides, arylamine-N-oxides such as triphenylamine-N-oxide, pyridine, 2-methylpyridine, 3-methyl Pyridines such as pyridine, 4-methylpyridine, 2-ethylpyridine, 3-ethylpyridine, 4-ethylpyridine, 4-dimethylaminopyridine, 4-methoxypyridine, 4-cyanopyridine, pyridine-N-oxide, 2- Methylpyridine-N-oxide, 3-methylpyridine-N-oxide, 4-methylpyridine-N-oxide, 2-ethylpyridine-N-oxide, 3-ethylpyridine-N-oxide, 4-ethylpyridine-N- Pyridine-N-oxides such as oxide, 4-dimethylaminopyridine-N-oxide, 4-methoxypyridine-N-oxide, 4-cyanopyridine-N-oxide, pyrrole, 2-methylpyrrole, 3-methylpyrrole, N-methylpyrrole, 2-ethylpyrrole, 3-ethylpyrrole, N-ethylpyrrole , N-trimethylsilylpyrrole, N-triethylsilylpyrrole, pyrroles such as N-tert-butyldimethylsilylpyrrole, imidazole, N-methylimidazole, 1,2-dimethylimidazole, 1,4-dimethylimidazole, 1,5 -Imidazole such as dimethylimidazole, N-ethylimidazole, Nn-propylimidazole, N-isopropylimidazole, Nn-butylimidazole, N-trimethylsilylimidazole, N-triethylsilylimidazole, N-tert-butyldimethylsilylimidazole , Triazole, N-methyltriazole, 1,3-dimethyltriazole, 1,5-dimethyltriazole, N-ethyltriazole, Nn-propyltriazole, N-isopropyltriazo , N-trimethylsilyltriazole, N-triethylsilyltriazole, triazoles such as N-tert-butyldimethylsilyltriazole, tetrazole, N-methyltetrazole, 1,5-dimethyltetrazole, N-ethyltetrazole, Nn- Tetrazoles such as propyltetrazole, N-isopropyltetrazole, N-trimethylsilyltetrazole, N-triethylsilyltetrazole, N-tert-butyldimethylsilyltetrazole, oxazole, 2-methyloxazole, 4-methyloxazole, 5-methyloxazole, 2 2,4-dimethyloxazole, 2,5-dimethyloxazole, 2,4,5-trimethyloxazole, 2-ethyloxazole, 4-ethyloxazole, 5-ethyloxax Oxazoles such as alcohol, isoxazole, 3-methylisoxazole, 4-methylisoxazole, 5-methylisoxazole, 3,4-dimethylisoxazole, 3,5-dimethylisoxazole, 3,4,5- Isoxazoles such as trimethylisoxazole, 3-ethylisoxazole, 4-ethylisoxazole, 5-ethylisoxazole, morpholine, N-methylmorpholine, N-ethylmorpholine, Nn-propylmorpholine, N-isopropylmorpholine Morpholines such as Nn-butylmorpholine, N-sec-butylmorpholine, N-tert-butylmorpholine, N-trimethylsilylmorpholine, N-triethylsilylmorpholine, N-tert-butyldimethylsilylmorpholine, etc. Morylline-N-oxides such as silylmorpholines, N-methylmorpholine-N-oxide, N-ethylmorpholine-N-oxide, diazabicycloundecene (DBU®), 1,5-diazabicyclo [4 , 3,0] -5-nonene (DBN) and the like. Particularly preferred bases are super strong bases such as i-Pr ₂ NEt, DBU (registered trademark), DBN and the like. The usage-amount of a base is 1-300 mol% normally with respect to 1 mol of compounds of Formula (1), Preferably it is 20-300 mol%, More preferably, it is 20-100 mol%.

  Although there is no restriction | limiting in particular in the usage-amount of the carbon dioxide used in this invention, Usually, it reacts on carbon dioxide atmosphere or carbon dioxide pressurization conditions. Among these, a preferable carbon dioxide pressure is from 0.1 MPa to 10 MPa, preferably from 0.1 MPa to 5 MPa, and more preferably from 0.1 MPa to 2 MPa. In addition, the reaction can be performed under a mixed gas of an inert gas and carbon dioxide that does not significantly affect the reaction such as nitrogen or argon.

The reaction temperature is from 0 ° C to 90 ° C, and particularly preferably from room temperature to 60 ° C. “Room temperature” means a temperature of 15 ° C. to 30 ° C.
The reaction time varies depending on the reaction conditions, but is usually 0.1 to 200 hours.
According to the above method, by reacting propargyl alcohol represented by the formula (1) with carbon dioxide in a polar solvent in the presence of a transition metal catalyst and a base, α, represented by the formula (2) A β-unsaturated carbonyl compound can be obtained. The α, β-unsaturated carbonyl compound represented by the formula (2) produced by this reaction can be purified and isolated by a known method such as column chromatography. However, the present invention is not limited to these examples.

Example 1
2-Methyl-6-phenyl-3-hexyn-2-ol (41.7 mg, 0.25 mmol) was dissolved in formamide (0.5 mL) and silver methanesulfonate (5.1 mg, 0.025 mmol) and DBU (7.5 mg, 0.050 mmol) was added, and the mixture was stirred at 60 ° C. for 8 hours under a 1.0 MPa carbon dioxide atmosphere. After completion of the reaction, the mixture was purified by silica gel column chromatography (EtOAc / hexane, 1:50) to give 5-methyl-1-phenyl-4-hexen-3-one as a colorless oil in 89% yield. It was.

Example 2
Α, β-unsaturated carbonyl compounds were synthesized using various solvents.
This reaction involves dissolving 2-methyl-6-phenyl-3-hexyn-2-ol (0.25 mmol) in various solvents (0.5 mL), silver methanesulfonate (10 mol%), and DBU ( 0.25 mmol) was added, and the reaction was performed at room temperature under a carbon dioxide atmosphere of 1.0 MPa.

Example 3
Synthesis of α, β-unsaturated carbonyl compounds was carried out under various bases and reaction conditions.
In this reaction, a substrate (0.25 mmol) was dissolved in formamide (0.5 mL), silver methanesulfonate (10 mol%) and various bases (equivalent to the substrate in parentheses) were added, and 1.0 MPa of carbon dioxide was added. It was performed at room temperature or 60 ° C. in an atmosphere.

Example 4
Α, β-unsaturated carbonyl compounds were synthesized using various propargyl alcohols.
This reaction was performed under a 1.0 MPa carbon dioxide atmosphere by dissolving a substrate (0.25 mmol) in formamide (0.5 mL), adding silver methanesulfonate (10 mol%) and DBU.
However, Examples 4 to 7 and 13 used i-Pr ₂ NEt as a base. In Examples 8 and 12, DMF was used as a polar solvent.
A to C in the column of conditions in Table 3 mean the following reaction conditions, respectively.
Condition A: Reaction was performed at 60 ° C. using 0.2 equivalent of DBU relative to the substrate.
Condition B: The reaction was carried out at room temperature using 1.0 equivalent of DBU relative to the substrate.
Condition C: Reaction was performed at 60 ° C. using 3.0 equivalents of DBU relative to the substrate.

Example 5
Using various gold salts as catalysts, α, β-unsaturated carbonyl compounds were synthesized.
In this reaction, 2-methyl-6-phenyl-3-hexyn-2-ol (0.25 mmol) was dissolved in methyl chloride (0.5 mL), AuX (10 mol%) and DBU (1 with respect to the substrate). .2 equivalents) was added and carried out at room temperature under a 0.1 MPa carbon dioxide atmosphere. However, Example 4 was carried out at 60 ° C. under methyl chloride (1 mL) and 2.0 MPa carbon dioxide atmosphere, and Example 5 was carried out at 60 ° C. under toluene (1 mL) and 2.0 MPa carbon dioxide atmosphere.
The isolated yield was measured by GC analysis.

  The α, β-unsaturated carbonyl compound obtained by the present invention is useful as a synthetic intermediate or raw material for physiologically active compounds such as pharmaceuticals, an organic solvent, or a raw material monomer for producing a polycarbonate resin.

Claims (16)

Formula (1)

(Where
R ¹ and R ² are the same or different and are a hydrogen atom or an organic group,
R ³ is a hydrogen atom or an organic group bonded directly or via oxygen)
By reacting propargyl alcohol represented by the following formula with carbon dioxide in a polar solvent in the presence of a transition metal catalyst and a base:

(Wherein R ¹ , R ² and R ³ are as defined above)
The manufacturing method of the (alpha), (beta)-unsaturated carbonyl compound represented by these. Formula (1)

{Where,
R ¹ and R ² are the same or different and each represents a hydrogen atom, a C _1-6 alkyl group [the C _1-6 alkyl group is unsubstituted or a C _6-12 aryl group (the C _6-12 The aryl group is unsubstituted or substituted with a C _1-6 alkyl group, a C _1-6 alkoxy group, a halogen atom, or a protected hydroxyl group), a C _1-6 alkoxy group, a halogen atom, Or substituted with a protected hydroxyl group], or a C _6-12 aryl group (the C _6-12 aryl group is unsubstituted or a C _1-6 alkyl group, a C _1-6 alkoxy group, Substituted with a halogen atom or a protected hydroxyl group), or R ¹ and R ² are bonded to each other to form C _3-8 cycloalkyl,
R ³ represents a hydrogen atom, a hydroxyl group, a C _1-6 alkyl group [the C _1-6 alkyl group is unsubstituted or a C _6-12 aryl group (the C _6-12 aryl group is Substituted or substituted with a C _1-6 alkyl group, a C _1-6 alkoxy group, a halogen atom, or a protected hydroxyl group), a C _1-6 alkoxy group, a halogen atom, or a protected hydroxyl group Substituted with a C _6-12 aryl group (the C _6-12 aryl group is unsubstituted or a C _1-6 alkyl group, a C _1-6 alkoxy group, a halogen atom, or a protected group). Substituted with a hydroxyl group), a C _1-6 alkoxy group (the C _1-6 alkoxy group is unsubstituted, a C _1-6 alkyl group, a C _1-6 alkoxy group, a halogen atom, or is substituted with a protected hydroxyl group), or C _6-12 aryloxy group (the _6-12 aryloxy group is unsubstituted or substituted by C _1-6 alkyl, C _1-6 alkoxy group is substituted with a halogen atom or a protected hydroxyl group)}
By reacting propargyl alcohol represented by the following formula with carbon dioxide in a polar solvent in the presence of a transition metal catalyst and a base:

(Wherein R ¹ , R ² and R ³ are as defined above)
The manufacturing method of the (alpha), (beta)-unsaturated carbonyl compound represented by these. R ¹ and R ² are the same or different and are a C _1-6 alkyl group, or R ¹ and R ² are bonded to each other and are C _3-8 cycloalkyl,
The manufacturing method of Claim 1 or 2. R ¹ and R ² are the same or different and are an unsubstituted C _1-6 alkyl group, or R ¹ and R ² are bonded to each other and are C _3-8 cycloalkyl,
The manufacturing method of any one of Claims 1-3. R ³ is a hydrogen atom, C _1-6 alkyl group, or a C _1-6 alkoxy group, The method according to any one of claims 1 to 4. R ³ is a hydrogen atom, a C _1-6 alkyl group [the C _1-6 alkyl group is unsubstituted, or a phenyl group (the phenyl group is unsubstituted, or C _1-6 alkyl Substituted with a group, a C _1-6 alkoxy group, a halogen atom, or a protected hydroxyl group)], or an unsubstituted C _1-6 alkoxy group. The production method according to claim 1. R ³ is a hydrogen atom, a C _1-6 alkyl group (the C _1-6 alkyl group is unsubstituted or substituted with an unsubstituted phenyl group), or an unsubstituted C _1-6 The manufacturing method of any one of Claims 1-6 which is an alkoxy group. R ¹ and R ² are the same or different and are an unsubstituted C _1-6 alkyl group, or R ¹ and R ² are bonded to each other to be C _3-8 cycloalkyl,
R ³ is a hydrogen atom, a C _1-6 alkyl group (the C _1-6 alkyl group is unsubstituted or substituted with an unsubstituted phenyl group), or an unsubstituted C _1-6 The manufacturing method of any one of Claims 1-7 which is an alkoxy group.   The production method according to any one of claims 1 to 8, wherein the polar solvent to be used is selected from the group consisting of formamide, dimethylformamide, dimethylacetamide, dichloromethane, and benzene chloride.   The production method according to claim 9, wherein the polar solvent used is formamide, dimethylformamide, or dimethylacetamide.   Catalysts used are silver methanesulfonate (I), gold (I) chloride, gold (III) chloride, sodium tetrachloroaurate (III) dihydrate, gold chlorotriphenylphosphine, tris (acetylacetonato) rhodium ( III), mercury triflate (II), platinum chloride (II), palladium chloride (II), palladium acetate (II), copper chloride (I), silver perchlorate (I), silver cyanide (I), trifluoromethane Silver sulfonate (I), silver carbonate (I), silver tetrafluoroborate (I), silver fluoride (I), silver hexafluorophosphate (I), silver hexafluoroantimonate (I), silver acetate ( The manufacturing method of any one of Claims 1-10 selected from the group which consists of I) and p-toluene sulfone silver (I).   The production method according to claim 11, wherein the catalyst used is silver (I) methanesulfonate or gold (III) chloride.   The production method according to any one of claims 1 to 12, wherein the base used is diisopropylethylamine, diazabicycloundecene, or 1,5-diazabicyclo [4,3,0] -5-nonene.   The process according to any one of claims 1 to 13, wherein the reaction temperature is from room temperature to 60 ° C.   Carbon dioxide pressure is 0.1MPa-2MPa, The manufacturing method of any one of Claims 1-14. A compound selected from the group consisting of the following, produced by the production method according to any one of claims 1 to 15:
5-methyl-1-phenyl-4-hexen-3-one;
5-ethyl-1-phenyl-4-hepten-3-one;
5-isopropyl-6-methyl-1-phenyl-4-hepten-3-one;
1-cyclopentylidene-4-phenyl-2-butanone;
1-cyclohexylidene-4-phenyl-2-butanone;
1-cycloheptylidene-4-phenyl-2-butanone;
1,5-diphenyl-4-hexen-3-one;
1,1-diphenyl-1-hexen-3-one;
1-phenyl-4-hexen-3-one;
1-phenyl-4-hepten-3-one;
1-phenyl-4-penten-3-one;
2-methyl-2-decen-4-one;
Ethyl 3-methyl-5-phenylpent-2-enoate; and ethyl 5-phenylpent-2-enoate.