Process for producing phenoxyalkene derivative

A phenoxyalkene derivative having the formula ##STR1## wherein R represents a hydrogen atom, ##STR2## and Y and Z are the same or different and respectively represent a hydrogen atom, trifluoromethyl group, a halogen atom, a lower alkyl group, nitro group or cyano group; R.sub.1 represents a hydrogen atom or a lower alkyl group and R.sub.2 represents carboxyl, hydroxymethyl, allyloxycarbonyl, a lower alkoxycarbonyl, a lower haloalkoxycarbonyl, a S-lower alkylthiocarbonyl, carbamoyl, a N-lower alkylcarbamoyl or a N-phenylcarbamoyl group is produced by reacting a phenol compound having the formula ##STR3## with a dihalogen compound having the formula ##STR4## wherein R, R.sub.1 and R.sub.2 are defined above and X.sub.1 represents a halogen atom and X.sub.2 and X.sub.3 are different and respectively represent a hydrogen atom or a halogen atom, by a simultaneous reaction of an etherification and an unsaturated double bond formation, in the presence of a dehydrogenhalide agent and a polar solvent or a combination of a nonpolar solvent and a quaternary ammonium salt or a quaternary phosphonium salt.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The present invention relates to a process for producing phenoxyalkene 
derivatives useful as agricultural chemicals. 
2. Description of the Prior Art 
It has been known that phenoxyalkene derivatives can be produced by 
reacting a phenol having the formula 
##STR5## 
wherein R.sub.3 represents hydrogen atom or 
##STR6## 
Y' and Z' are the same or different and respectively represent hydrogen 
atom, trifluoromethyl group, a halogen atom, or lower alkyl group, nitro 
group or cyano group, with a monohalogen compound having the formula 
##STR7## 
wherein R.sub.4 represents a lower alkyl group; R.sub.5 represents 
carboxyl, hydroxymethyl, allyloxycarbonyl, a lower alkoxycarbonyl, a lower 
haloalkoxycarbonyl, a S-lower alkylthiocarboxyl, carbamoyl, a N-lower 
alkylcarbamoyl or a N-phenylcarbamoyl group in a solvent such as ketones 
e.g. acetone, and methylethyl ketone, ethers such as tetrahydrofuran, 
diethyl ether, methyl butyl ether, ethyleneglycol dimethyl ether; 
dimethylformamide, dimethylacetamide, dimethylsulfoxide, benzene, toluene 
and hexane, etc. in the presence of a dehydrogenhalide agent such as an 
alkali metal compound e.g. sodium or potassium compound or an alkaline 
earth metal compound e.g. calcium or magnesium compound. 
However, a dehydrogenhalidation of the monohalogen compound is caused by 
this process. Thus, a large amount of the monohalogen compound should be 
used and a large amount of the by-products is produced to cause low yield 
of the object compound. 
The inventors have studied to obtain a phenoxyalkene derivative having high 
purity in high yield. Thus, the special reaction mechanism of combination 
of an etherification and an unsaturated double bond formation in one step 
has been found. 
SUMMARY OF THE INVENTION 
It is an object of the present invention to produce a phenoxyalkene 
derivative having high purity in high yield by a special reaction 
mechanism. 
The foregoing and other objects of the present invention have been attained 
by reacting a phenol compound having the formula 
##STR8## 
wherein R represents a hydrogen atom, 
##STR9## 
and Y and Z are the same or different and respectively represent a 
hydrogen atom, trifluoromethyl group, a halogen atom, a lower alkyl group, 
nitro group or cyano group; with a dihalogen compound having the formula 
##STR10## 
wherein R.sub.1 represents a hydrogen atom or a lower alkyl group; R.sub.2 
represents carboxyl, hydroxymethyl, allyloxycarbonyl, a lower 
alkoxycarbonyl, a lower haloalkoxycarbonyl, a S-lower alkylthiocarboxyl, 
carbamoyl, a N-lower alkylcarbamoyl or a N-phenylcarbamoyl group; X.sub.1 
represents a halogen atom, X.sub.2 and X.sub.3 are different and 
respectively represent a hydrogen atom or a halogen atom in a solvent in 
the presence of a dehydrogenhalide agent of an alkali metal compound or an 
alkaline earth metal compound to obtain a phenoxyalkene derivative having 
the formula 
##STR11## 
wherein R, R.sub.1 and R.sub.2 are defined above. 
It is preferable to add a quarternary ammonium salt such as benzyltrialkyl 
ammonium salt and tetraalkyl ammonium salt or a quaternary phosphonium 
salt such as benzyltrialkyl phosphonium salt and tetraalkyl phosphonium 
salt in a nonpolar solvent. 
It is also preferable to carry out the reaction in a polar solvent without 
a quaternary salt. 
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
The reaction mechanism of the present invention is a novel mechanism of a 
combination of an etherification and an unsaturated double bond formation. 
The phenols having the formula (I) are the compounds having the formula 
##STR12## 
wherein Y and Z are the same or different and respectively represent a 
hydrogen atom, trifluoromethyl group, a halogen atom such as chlorine, 
bromine, fluorine or iodine atom; a lower alkyl group e.g. methyl, ethyl, 
propyl, isopropyl, butyl and isobutyl group; nitro group and cyano group. 
The dihalogen compounds used in the present invention include the compounds 
having the formula (II) wherein R.sub.1 represents a hydrogen atom; a 
lower alkyl group such as methyl, ethyl, propyl, isopropyl, butyl and 
isobutyl group; R.sub.2 represents carboxyl, hydroxymethyl, 
allyloxycarbonyl; a lower alkoxycarbonyl such as methoxycarbonyl, 
ethoxycarbonyl, isopropoxycarbonyl and sec.-butoxycarbonyl group; a lower 
haloalkoxycarbonyl group such as .beta.-chloroethoxycarbonyl, 
.beta.-bromoethoxycarbonyl, .alpha.,.beta.-dibromopropyloxycarbonyl, and 
.beta., .beta.'-dibromoisopropyloxycarbonyl group; a S-lower 
alkylthiocarboxyl group such as S-methylthiocarboxyl, S-ethylthiocarboxyl 
and S-butylthiocarboxyl group; carbamoyl group; a N-lower alkylcarbamoyl 
group such as N-methylcarbamoyl, N-ethylcarbamoyl, N-isopropylcarbamoyl 
and N-isobutylcarbamoyl group; N-phenylcarbamoyl group; X.sub.1 represents 
a halogen atom and X.sub.2 and X.sub.3 are different and respectively 
represent a hydrogen atom or a halogen atom. 
When the reaction of the present invention is carried out in a polar 
solvent, the polar solvent can be a lower alcohol such as methanol and 
ethanol; ketones such as acetone, methylethyl ketone; ethers such as 
tetrahydrofuran, diethyl ether, methyl butyl ether, ethyleneglycol 
dimethylether, dimethylformamide, dimethylacetamide, and 
dimethylsulfoxide. 
Sometimes, it is preferable to add a quaternary ammonium salt or a 
quaternary phosphonium salt such as benzyltrialkylammonium salts, 
benzyltrialkylphosphonium salts, tetraalkylammonium salts and 
tetraalkylphosphonium salts, for example, benzyltriethylammonium bromide, 
benzyltributylammonium chloride, benzyltriamylammonium chloride, 
benzyltrioctylammonium chloride, trioctylmethylammonium chloride, 
isobutyltributylammonium bromide, hexadecyltributylphosphonium bromide, 
tetrapropylammonium bromide, tetrabutylammonium bromide, 
tetrabutylammonium chloride, tetraamylammonium bromide, tetraamylammonium 
chloride, tetrahexylammonium bromide, tetrabutylphosphonium chloride, 
benzyltributylphosphonium chloride, benzyltriphenylphosphonium chloride, 
methyltriphenylphosphonium bromide and tetraphenylphosphonium chloride. It 
is preferable to select the quaternary ammonium salt or the quaternary 
phosphonium salt from benzyl tri-C.sub.1 -C.sub.16 alkylammonium salts, 
tetra-C.sub.1 -C.sub.16 alkylammonium salts, triphenyl C.sub.1 -C.sub.16 
alkylammonium salts, benzyl tri-C.sub.1 -C.sub.16 alkylphosphonium salts, 
tetra-C.sub.1 -C.sub.16 alkylphosphonium salts, and triphenyl C.sub.1 
-C.sub.16 alkylphosphonium salts. 
The alkali metal compounds or alkaline earth metal compounds used in the 
reaction can be potassium hydroxide, sodium hydroxide, potassium 
carbonate, sodium carbonate and sodium bicarbonate. 
It is preferable to use a solvent so as to smoothly perform the reaction, 
especially to use a solvent being stable in the reagents including the 
alkali metal compound and the alkaline earth metal compound. 
In the reaction of the present invention, the dihalogen compound (II) is 
used at a molar ratio of 1.0 to 1.5 preferably 1.05 to 1.1 based on the 
phenol compound (I). 
The alkali metal compound or the alkaline earth metal compound as a base is 
used at a molar ratio of 1 to 3 based on the phenol compound (I). The 
alkali metal compound or the alkaline earth metal compound can be used as 
an aqueous solution. 
The quaternary ammonium salt or the quaternary phosphonium salt is used as 
a molar ratio of 0.005 to 0.05 preferably 0.008 to 0.015 based on the 
phenol compound (I). 
In the reaction of the phenol compound (I) with the dihalogen compound 
(II), the reaction temperature can be 30.degree. to 150.degree. C. 
preferably 60.degree. to 120.degree. C. in a polar solvent and 50.degree. 
to 90.degree. C. preferably 60.degree. to 80.degree. C. in a nonpolar 
solvent presence of a quaternary salt. 
The reaction time can be in a range of 4 to 8 hours. When the quaternary 
salt is used, after the reaction, the water phase is separated and the 
organic phase is washed with an acid and then with water and then, the 
solvents are removed by a distillation under a reduced pressure to obtain 
the object compound of the phenoxyalkene derivative (III). 
When the quaternary salt is not used, a polar solvent is used, after the 
reaction, the solvent is distilled off and the resulting product was 
dissolved in a nonpolar solvent such as benzene, toluene, chlorobenzene 
and the solution is washed with water. The water phase is separated and 
the resulting organic phase is washed with an acid and then with water and 
then, the solvents are removed by a distillation under a reduced pressure 
to obtain the object compound of the phenoxyalkene derivative (III). 
When the dihalogen compound (II) is not an ester, after the reaction, a 
conc. hydrochloric acid is added with stirring to be acidic and the water 
phase is separated and then, the solvent is distilled off to obtain the 
phenoxyalkene derivative (III). 
In accordance with the process of the present invention, the phenol 
compound (I) and the dihalogen compound having saturated hydrocarbon chain 
(II) is used to react them in a novel reaction mechanism for preventing a 
side reaction and performing the etherification and the unsaturated double 
bond formation, whereby the object compound of the phenoxyalkene 
derivative having high purity can be obtained in high yield.