TECHNICAL FIELD
The present invention relates to a new l-acetoxy-3-(substituted phenyl)propene compounds. More particularly, the present invention relates to a new 1-acetoxy-3-(substituted phenyl)propene compounds having a phenyl group substituted with an alkylenedioxy group, and located in the 3-position of the propene compound.
The l-acetoxy-3-(substituted phenyl)propene compound^ are useful as an intermediate material for perfumes, pharmaceuticals, agricultural chemicals and other organic synthetic chemicals. BACKGROUND ART
Bull, Soc, Chim, Frame, 1961, pll95 - 1198, discloses, as a process for synthesizing a l-acetoxy-3-(substituted phenyl)propene compound, a process for synthesizing l-acetoxy-3-(3,4-dimethoxyphenyl)propene by reacting 1,2-dimethoxybenzene with an alkenylidene diacetate in the presence of titanium tetrachloride activated with a boron trifluoride-ether complex. This literature reported that the yield of the target compound produced by this process was 62%, which was unsatisfactory. The inventors of the present invention tried to trace the process of the above-mentioned literature, and as a result, found that the yield of the target compound was only 12%, a plurality of by-products were produced, and the resultant product mixture liquid exhibited a brown color (refer to Comparative Example 3 of the present application). Also, it was confirmed that titanium tetrachloride, used for the process of the literature, was a chemically unstable compound to such an extent that this compound is decomposed by moisture in the atmospheric air, and thus complicated and meticulous

care is needed in handling this compound.
Further, the inventors of the present invention tried to apply the process of the literature to the reaction of 3,4-methylenedioxy benzene with an alkenylidene diacetate and found that the titanium tetrachloride activated by boron trifluoride-ether complex caused a decomposition reaction of 3,4-methylenedioxybenzene to be promoted, and the yield of the target compound was 43% and unsatisfactory (refer to Comparative Example 1 of the present application). Furthermore, the inventors of the present invention tried to effect the reaction by using titanium tetrachloride in an amount of 0.1 mole per mole of alkenylidene diacetate, to control or prevent the decomposition of 3,4-methylenedioxybenzene. As a result, the yield of the target compound decreased to 9.8% (refer to Comparative Example 2 of the present application).
Japanese Unexamined Patent Publication No. 55-141437 discloses a process for producing l-acetoxy-2-methyl-3-(4-t-butylphenyl)propene by reacting t-butylbenzene with methacrolein and acetyl chloride in the presence of a stoichiometric amount of a Lewis acid. In this process, when titanium tetrachloride was used as Lewis acid, the yield of the target compound was 46.2%, and when boron trifluoride-ether complex was employed as a Lewis acid, the yield of the target compound was 2.3%. In each of the above-mentioned cases, the target compound yield was low and unsatisfactory. DISCLOSURE OF THE INVENTION
An object of the present invention is to provide new l-acetoxy-3-(substituted phenyl)propene compounds useful as an intermediate material, for perfumes,
pharmaceuticals, agricultural chemicals and other organic synthetic chemicals.
The above-mentioned object can be attained by the 1-acetoxy-3-(substituted phenyl)propene compound of the present invention.

Insert the passage in Attachment (6)
The l-acetoxy-3-(substituted phenyl)propene
compounds of the present invention represented by the
general formula (I):

(Formula Removed)
in which formula (I), R1 and R2, respectively and independently from each other, represent a member selected from the groups consisting of a hydrogen atom and alkyl groups having 1 to 10 carbon atoms, R1 and R2 may form, together with carbon atoms located in the 2-and 3-positions of the propene group, a cyclic group; and A represents a member selected from a group of substituted phenyl groups represented by the formula (III) :

(Formula Removed)
wherein,
can be produced by the process comprising reacting a benzene compound selected from those represented by the general formula (VI):

(Formula Removed)
in which formula (VI), k is as defined above, with an alkenylidene diacetate compound represented by the general formula (VII):

(Formula Removed)

in which formula (VII), R1 and R2 are as defined above,
in the presence of a catalyst comprising at least one compound selected from the group consisting of (a) halogenated boron compounds, (b) triflate compounds of Group 11 elements of the Periodic Table, (c) halogenated compounds of Group 12 elements of the Periodic Table, and (d) triflate compounds and halogenated compounds of tin and lanthanoid elements of atomic numbers 58 and 66 to 71.
In the process for producing the l-acetoxy-3-(substituted phenyl)propene compound, the benzene compounds represented by the formula (VI) is preferably selected from the group consisting of 1,2-methylenedioxybenzene and 1,2-ethylenedioxybenzene.
In the process for producing the l-acetoxy-3-(substituted phenyl)propene compound, the alkenylidene diacetate is preferably selected from the group consisting of 3,3-diacetoxy-2-methylpropene, 3,3-diacetoxy propene, 3,3-diacetoxy-l-methylpropene, 3,3-diacetoxy-2-ethyl propene, 3,3-diacetoxy-l-ethylpropene, and 3,3-diacetoxy-l-ethyl-2-methylpropene.
In the process for producing the l-acetoxy-3-(substituted phenyl)propene compound, the reaction is preferably carried out in a molar ratio of the benzene compound to the alkenylidene diacetate compound of 1:1 to 50:1.

In the process for producing the l-acetoxy-3-(substituted phenyl)propene compound, the catalyst is preferably present in an amount of 0.005 to 1 mole per mole of the alkenylidene diacetate compound.
In the process for producing the l-acetoxy-3-(substituted phenyl)propene compound, the halogenated boron compounds (a) usable for the catalyst are preferably selected from boron fluorides, boron trifluoride-diethylether complexes, borontrifluoride-tetrahydrofuran complexes, boron trifluoride-acetic acid complex salt, boron trifluoride dihydrate, and boron trifluoride-n-butylether complexes.
In the process for producing the l-acetoxy-3-(substituted phenyl)propene compound, the triflate compounds (b) of Group 11 elements of the Periodic Table usable for the catalyst are preferably selected from the group consisting of copper triflate and silver triflate.
In the process for producing the l-acetoxy-3-(substituted phenyl)propene compound, the harogenated compounds (c) of Group 12 elements of the Periodic Table usable for the catalyst are preferably selected from the group consisting of zinc fluoride, zinc chloride, zinc bromide, zinc iodide, cadmium fluoride, cadmium chloride, cadmium bromide, cadmium iodide, hydrogen fluoride, mercury chloride, mercury bromide, and mercury iodide.
In the process for producing the l-acetoxy-3-(substituted phenyl)propene compound, the triflate and halogenated compounds (d) of tin and lanthanoid elements of atomic numbers 58 and 66 to 71 are preferably selected from the group consisting of triflates, fluorides, chloride, bromides, and iodide of tin, cerium, dysprosium, holmium, erbium, thulium, ytterbium and lutetium.
In the process for producing the l-acetoxy-3-(substituted phenyl)propene compound, the reaction is preferably carried out in an atmosphere consisting of a nonreactive gas to the above-mentioned compounds of the

formulae (VI) and (VII), the above-mentioned catalyst and the resultant reaction products.
The compounds represented by the formula (I) are new compounds.
The compound of the formula (I) is preferably selected from l-acetoxy-3-(3,4-C1 to C2 alkylene dioxyphenyl)propenes represented by the formulae (X) and (XI) :

(Formula Removed)

The compounds represented by the formulae (X) and (XI) are new compounds.
In the l-acetoxy-3-(substituted phenyl)propene compound of the present invention, preferably in the formulae (X) and (XI), R1 represents a hydrogen atom and R2 represents a methyl group.
In the l-acetoxy-3-(substituted phenyl)propene compound of the present invention, the compound of the formula (I) is preferably selected from the groups consisting of l-acetoxy-2-methyl-3-(3, 4-methylenedioxyphenyl)propene, and l-acetoxy-2-methyl-3-(3,4-ethylenedioxyphenyl)propene.
The above-mentioned l-acetoxy-2-methyl-3-(3,4-methylenedioxyphenyl)propene, and l-acetoxy-2-methyl-3-(3,4-ethylenedioxyphenyl)propene, are new compounds.
The Periodic Table used in the present invention is based on the 18 Groups-Type Elemental Periodic Table,

IUPAC and Nomenclature in Inorganic Chemistry, 1990 Rule.
Also, the term "triflate" refers to trifluoromethanesulfonate. BEST MODE FOR CARRYING OUT THE INVENTION
The l-acetoxy-3-(substituted phenyl)propene compound produced by the process of the present invention is represented by the above-mentioned general formula (I) and includes a plurality of types of stereoisomers due to asymmetric carbon atoms and/or a double bond contained in the molecule of the compound.
The process for producing l-acetoxy-3-(substituted phenyl)propene compound of the present invention comprises the step of reacting at least one member selected from a group of benzene compounds represented by the above-mentioned general formula (VI) with an alkenylidene diacetate represented by the general formula (VII) in the presence of a specific catalyst which will be illustrated in detail hereinafter. The benzene compounds represented by the formula (VI) correspond to the substituted phenyl groups represented by the general formula (III), and the alkenylidene diacetate of the general formula (VII) corresponds to a 1-acetoxypropene group bonded to the A group contained in the general formula (I).
The specific catalysts for the process of the present invention comprises at least one member selected from the group consisting of:
(a) halogenated boron compounds,
(b) triflate compounds of Group 11 elements of the Periodic Table,
(c) halogenated compounds of Group 12 elements of the Periodic Table, and (d) triflate compounds and halogenated compounds of tin and lanthanoid elements of atomic number 58 and 66 to 71.
The benzene compound represented by the general formula (VI) is preferably selected from 1,2-methylenedioxybenzene and 1,2-ethylenedioxybenzene.

Further, the alkenylidene diacetate represented by the general formula (VII) is preferably selected from the group consisting of 3,3-diacetoxy-2-methylpropene, 3,3-diacetoxy-propene, 3,3-diacetoxy-l-methylpropene, 3,3-diacetoxy-2-ethylpropene, 3,3-diacetoxy-l-ethylpropene and 3,3-diacetoxy-l-ethyl-2-methylpropene. These compounds may be in trade grade and, optionally may be prepared with an α, ß-unsaturated aldehyde and acetic anhydride in accordance with the process disclosed in Bull, Soc, Chim, Frame, 1961, pll94 to 1198. These compounds include isomers.
In the alkenylidene diacetate represented by the general formula (VII) , groups R1 and R2 may be bonded to each other to form, together with the carbon atoms in the 2- and 3-positions of the propene group, a cyclic group.
The cyclic group is preferably a cyclopentane or cyclohexane group, more preferably a cyclohexane group.
The α,ß-unsaturated aldehyde usable for the preparation of the alkenylidene diacetate preferably include acrolein, methacrolein, crotonaldehyde, α, ß-dimethylacrolein, a-ethylacrolein, P-ethylacrolein, ß-propylacrolein and a-cyclohexylacrolein, more preferably acrolein, methacrolein and crotonaldehyde, still more preferably methacrolein.
The halogenated boron compound (a) for the catalyst usable for the process of the present invention includes, for example, boron fluoride, boron trifluoride-diethylether complex, boron trifluoride-tetrahydrofuran complex, boron trifluoride-acetic acid complex salt, boron trifluoride-dihydrate and boron trifluoride-n-butylether complex. Among them, boron trifluoride-ether complex and boron trifluoride-acetic acid complex salt are more preferably employed. These compounds may be of a trade grade.
The triflate compound of the Group 11 elements for the catalyst is preferably selected from copper triflate

and silver triflate.
The halogenated compounds (c) of the Group 12 elements for the catalyst preferably include zinc fluoride, zinc chloride, zinc bromide, zinc iodide, cadmium fluoride, cadmium chloride, cadmium bromide, cadmium iodide, mercury fluoride, mercury chloride mercury bromide and mercury iodide. Among them, the halogenated compounds of zinc are more preferably employed, and zinc chloride is still more preferably employed.
The triflate compounds and halogenated compounds (d) of tin and atomic number 58 and 66 to 71 lanthanoid elements preferably include tin triflate, tin fluoride, tin chloride, tin bromide, tin iodide, cerium fluoride, cerium chloride, cerium bromide, cerium iodide, cerium triflate, dysprosium fluoride, dysprosium chloride, dysprosium bromide, dysprosium iodide, dysprosium triflate, holmium fluoride, holmium chloride, holmium bromide, holmium iodide, holmium triflate, erbium fluoride, erbium chloride, erbium bromide, erbium iodide, erbium triflate, thulium fluoride, thulium chloride, thulium bromide, thulium iodide, thulium triflate, ytterbium fluoride, ytterbium chloride, ytterbium bromide, ytterbium iodide, ytterbium triflate, lutetium fluoride, lutetium chloride, lutetium bromide, lutetium iodide, lutetium triflate, and hydrates of the above-mentioned compounds. Among them, tin chloride, tin triflate, erbium triflate, thulium triflate, ytterbium chloride, ytterbium triflate and lutetium triflate are more preferably employed. Still more preferably, tin chloride and ytterbium chloride are employed.
In the above-mentioned process, the catalyst is preferably employed in an amount of 0.005 to 1 mole, more preferably 0.01 to 0.5 mole, still more preferably 0.01 to 0.2 mole, per mole of the alkenylidene diacetate. If the catalyst is used in an amount of more than 1 mole, complicated procedures may needed for recovery,

decomposition and disposal of the catalyst after the reaction is completed, and may cause the practice of the process of the present invention in the industrial scale to be inconvenient. Also, if the amount of the catalyst is less than 0.005 mole, the reaction may not be completed within a practical time, for example, within 24 hours.
The reaction in the process as mentioned above may be carried out in a solvent medium. Usually, the reaction is preferably not carried out in a solvent medium. For the solvent, aromatic hydrocarbons, for example, benzen and toluene, xylene; halogenated aromatic hydrocarbons, for example, chlorobenzene; and halogenated aliphatic hydrocarbons, for example, methylene chloride and dichloroethane, may be employed.
The reaction temperature for the above-mentioned process can be appropriately established in response to the types and concentrations of the starting compounds and catalysts. Usually, the reaction is carried out at a
temperature of -10 to 80°C, more preferably 0 to 60°C. The reaction time for the process of the present invention can be appropriately established in consideration of the types and concentrations of the starting compounds and catalysts and the reaction temperature. Usually, the reaction time is preferably in the range of from 0.5 to 24 hours, more preferably 0.5 to 12 hours.
There is no specific limitation to the type of the reaction atmosphere for the process as mentioned above. Usually, the reaction of the process is carried out in a gas nonreactive to the starting compounds (namely, the compounds of the general formulae (I) and (III)), the catalyst and the resultant products, for example, a gas atmosphere or flow comprising at least one gas selected from nitrogen gas and inert gases, for example, argon gas. The reaction is usually carried out at the ambient atmospheric pressure. However, the reaction pressure is

not limited to that mentioned above.
The l-acetoxy-3-(substituted phenyl)propene compound produced in accordance with the process is usually refined by separating the compound from the resultant reaction mixture liquid after the reaction is completed by a usual separate-recovery procedure, for example, an extraction, a concentration and a filtration and then optionally by applying a refining procedure, for example, a distillation, recrystallization and various chromatographies, to the separate-recovered fraction.
In the general formula (I) representing the 1-acetoxy-3-(substituted phenyl)propene compound produced by the process, R1 and R2 represent a hydrogen atom or a C1-C10 alkyl group, and preferably, at least one of R1 and R2 represents a C1-C10 alkyl group. The C1 - C10 alkyl groups represented by R1 and R2 include methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl and decyl groups. These groups respectively include a plurality of isomers. The alkyl group represented by R1 and R2 is preferably a methyl group.
In the general formula (I), the alkyl groups represented by R1 and R2 may be bonded (or fused) at the terminals thereof to each other to form, together with the carbon atoms located in the 1- and 2-positions of the propene group, a cyclic group. The cyclic group is preferably, for example, a cyclopentane or cyclohexane group, more preferably a cyclohexane group.
The compounds produced by the process, as mentioned above are the l-acetoxy-3-(substituted phenyl)propene compounds represented by the general formula (I):

(Formula Removed)

wherein, R1, R2 are as defined above, A represents a member selected from a group of substituted phenyl groups represented by the formulae (III):

(Formula Removed)

wherein k is as defined above, are novel compounds.
In the case where the A in the general formula (I) represents the substituted phenyl groups of the general formula (III), the l-acetoxy-3-(substituted phenyl)propene compounds of the present invention represented by the general formula (I) is preferably selected from the l-acetoxy-3-(3,4-Cl-C2alkylenedioxy-phenyl)propenes represented by the general formulae (X) and (XI). In this case, in the general formulae (X) and (XI), preferably, R1 represents a hydrogen atom and R2 represents a methyl group.
Accordingly, the l-acetoxy-3-(substituted phenyl)propene compounds of the present invention represented by the general formula (I) are preferably selected from the group consisting of l-acetoxy-2-methyl-3-(3,4-methylenedioxyphenyl)propene and l-acetoxy-2-methy1-3-(3,4-ethylenedioxyphenyl)propene. EXAMPLES
The present invention will be further illustrated by the following examples which are not intended to limit the scope of the present invention in any way.
In the examples, the yield of l-acetoxy-2-methyl-3-(substituted phenyl)propene was calculated on the basis of mass of 3,3-diacetoxy-2-methylpropene employed. Example 1
In an argon gas atmosphere at a temperature of 20°C, a 20 ml flask was charged with a mixed solution of 6.83g

We Claim:
1. l-acetoxy-3-(substituted phenyl) propene compounds represented by the general formula (I):

(Formula Removed)
in which formula (I), R1 and R2 respectively and independently from each other represent a member selected from the groups consisting of a hydrogen atom and alkyl groups having 1 to 10 carbon atoms, R1 and R2 may form, together with carbon atoms located in the 2- and 3-positions of the propene group, a cyclic group; and A represents a substituted phenyl groups represented by the formula (III):
(Formula Removed)


wherein k represents an integer of 1 or 2.
2. The l-acetoxy-3-(substituted phenyl)propene compounds as claimed in claim 1, selected from l-acetoxy-3-(3,4-Cl to C2 alkylene dioxyphenyl)propenes represented by the formulae (IV) or (V):

(Formula Removed)



in which formulae (IV) and (V) , R1 and R2 are as defined above.
3. The l-acetoxy-3-(substituted phenyl)propene compounds as claimed in claim 2, wherein in the formulae (IV) and (V), R1 represents a hydrogen atom and R2 represents a methyl group.
4. The l-acetoxy-3-(substituted phenyl)propene compounds as claimed in claim 1, selected from the group consisting of:
l-acetoxy-2-methyl-3-(3,4-methylenedioxyphenyl)propene; and
l-acetoxy-2-methyl-3-(3,4-ethylenedioxyphenyl)propene.