BE828372A - PROCESS FOR THE PREPARATION OF OXO COMPOUNDS - Google Patents

Description

       

  Process for the preparation of oxo compounds

  
 <EMI ID = 1.1>

  
 <EMI ID = 2.1>

  
be catalytically isomerized into α, β-unsaturated ketones or aldehydes in a very simple manner with good yield

  
and a high conversion rate by isomerization in the presence of a catalyst of hydroxycarbyl-siloxy-vanadium oxide under the addition of a hydrocarbyl-silanol, at least one phenyl group substituted by withdrawing groups of one or more electrons being present in the catalyst and / or the silanol.

  
The catalysts used up to now in this isomerization have the drawback of being relatively unstable and of not being able to be used once or a few times. The system composed of the catalyst and the silanol used in this invention, on the other hand, is much more stable and allows a large number of isomerizations to be carried out without changing the catalyst. With this catalytic system, isomerizations can be carried out in a relatively short time and in a temperature range of about 20 to 150 [deg.], Which can be of decisive importance with starting substances and thermolabile end compounds.

  
The invention is based on this finding and relates to

  
a process for the preparation of oxo compounds of general formula

  

 <EMI ID = 3.1>


  
 <EMI ID = 4.1>

  
or a lower alkyl group, R2 represents an alkyl or alkenyl radical which can be bonded with

  
a cycloalkyl, cycloalkenyl or phenyl radical,

  
or a cycloalkyl, cycloalkenyl or phenyl radical;

  
 <EMI ID = 5.1>

  
cycloalkenyl, which in turn can be condensed

  
r <EMI ID = 6.1>

  
or an alkyl or alkenyl radical which can be linked with a cycloalkyl, cycloalkenyl or phenyl radical, or a cycloalkyl, cycloalkenyl or phenyl radical; the alkyl, alkenyl, cycloalkyl, cycloalkenyl and phenyl radicals mentioned being optionally substituted by -lower alkyl, lower alkoxy, hydroxy, lower alkanoyl, aroyl, lower alkanoyloxy, or aroyloxy, or [except for the phenyl group] by an oxo or oxo ketalised group,

  
by catalytic isomerization of a tertiary carbinol of general formula

  

 <EMI ID = 7.1>


  
 <EMI ID = 8.1>

  
tion as above.

  
The process is characterized in that the isomerization is carried out with a catalyst of general formula

  

 <EMI ID = 9.1>


  
in which KW represents a hydrocarbon radical from the series of lower alkyl, cycloalkyl, phenyl or phenyl-lower alkyl, the phenyl radical possibly being substituted by one or more electron withdrawing groups, R represents a

  
 <EMI ID = 10.1>

  
n = 0, 1 or 2, and m + n = 3, <EMI ID = 11.1>

  

 <EMI ID = 12.1>


  
where KW, m and n have the same meaning as above,

  
the catalyst of general formula III and / or the silanol of general formula IV having at least one phenyl radical containing one or more electron withdrawing groups.

  
Of particular importance are the following groups of catalysts covered by general formula III:

  
Catalysts of general formula

  

 <EMI ID = 13.1>


  
in which m and n have the same meaning as

  
 <EMI ID = 14.1>

  
from the series of lower alkyl, cycloalkyl phenyl or phenyl-lower alkyl, R 'represents the group KW' or the radical -Si (KW ') 3,

  
as well as catalysts of general formula

  

 <EMI ID = 15.1>


  
in which m and n have the same meaning as above, KW "represents a phenyl radical substituted by one or more electron withdrawing groups and R" = KW "or KW '.

  
..,.

  
 <EMI ID = 16.1>

  
1

  
Silanols of general formula

  

 <EMI ID = 17.1>


  
in which m, n, KW "and R" have the same meaning as above,

  
as well as the silanols of general formula

  

 <EMI ID = 18.1>


  
 <EMI ID = 19.1>

  
as above.

  
 <EMI ID = 20.1>

  
 <EMI ID = 21.1>

  
carbon, for example methyl, ethyl, propyl, isopropyl, etc.

  
 <EMI ID = 22.1>

  
 <EMI ID = 23.1>

  
contain up to 30 carbon atoms.

  
 <EMI ID = 24.1>

  
lower limbs, preferably the methyl group, among the upper limbs preferably having an isoprene or similar structure, the radicals:

  
 <EMI ID = 25.1>

  
5-ethyl-4-methyl-pent-3-enyl,

  
4-hydroxy-4-methyl-pentyl,

  
4-methoxy-4-methyl-pentyl,

  
4,8-dimethyl-nona-3,7-dienyl,

  
4,8,12-trimethyl-tridecyl as well as 4,8,12-trimethyl-tridéca-3,7,11-trienyl.

  
As examples of radicals R2 representing a cycloalkyl and cycloalkenyl group, the following may be mentioned:

  
cyclohex-1-yl,

  
2,6,6-trimethyl-cyclohex-1-yl, 3-methyl-cyclohex-3-en-1-yl, and 4-methyl-cyclohex-3-en-1-yl.

  
The optionally substituted cyclcalcoyl component

  
 <EMI ID = 26.1>

  
hold up to 20 carbon atoms. As examples of such cycloalkyl radicals linked to saturated or unsaturated, branched or unbranched R2 radicals, preferably alkyl of isoprene structure or the like, there may be mentioned:

  
 <EMI ID = 27.1>

  
2- (4-oxo-2,6,6-trimethyl-cyclohex-1-en-1-yl) -vinyl, 2- (4,4-ethylenedioxy-2,6,6-trimethyl-cyclohex-1-en -lyl) -vinyl,

  
6- (2,6,6-trimethyl-cyclohex-1-en-1-yl) -4-methyl-hexa1,3,5-trienyl,

  
6- (4-oxo-2,6,6-trimethyl-cyclohex-1-en-1-yl) -4-methylhexa-1,3,5-trienyl, as well as

  
6- (4,4-ethylenedioxy-2,6.6-trimethyl-cyclohex-1-en-1yl) -4-methyl-hexa-1,3,5-trienyl,

  
 <EMI ID = 28.1>
- among the lower limbs the radicals <EMI ID = 29.1>

  
As examples of starting compounds of general formula

  
 <EMI ID = 30.1>

  
form a saturated or unsaturated, optionally substituted cycloalkyl radical, mention may be made of:

  
1-ethynyl-cyclopentanol,

  
1-ethynyl-cyclohexanol,

  
1-ethynyl-2,6,6-trimethyl-cyclohexanol,

  
4-ethynyl-4-hydroxy-1-oxo-3,5,5-trimethyl-cyclohex2-ene, and

  
 <EMI ID = 31.1>

  
cyclohex-2-ene.

  
As examples of starting compounds of general formula

  
 <EMI ID = 32.1>

  
which is condensed on its side with a saturated or unsaturated cycloalkyl radical, mention may be made of:

  
Pregn-5-en-20-yne-3 &#65533;, 17-diol,

  
 <EMI ID = 33.1>

  
13-ethyl-17-hydroxy-18,19-di-nor-17a-pregn-4-en-20-yn3-one [Norgestrel], and

  
 <EMI ID = 34.1>

  
[Mestranol].

  
The above ring system formed by the substituents

  
 <EMI ID = 35.1>

  
As substituents for the alkyl, alkenyl, cycloalkyl, cycloalkenyl and phenyl mentioned above, the following are taken into account: lower alkyl radicals containing from 1 to 6 carbon atoms such as methyl, ethyl, propyl, isopropyl, etc:; lower alkoxy radicals containing 1 to 6 carbon atoms such as methoxy, ethoxy, <EMI ID = 36.1>

  
propionyl, butyryl, etc. ; aroyl radicals, in particular benzoyl; lower alkanoyloxy radicals containing from 1 to 6 carbon atoms such as acetyloxy, propionyloxy, butyryloxy, etc; aroyloxy radicals, in particular benzoyloxy.

  
An oxo group can be ketalized by lower alkanols or glycols, for example methanol or ethylene glycol.

  
The radical represented by KW in the general formula III preferably represents a lower alkyl group containing up to 7 carbon atoms, for example methyl, ethyl, isopropyl or n-butyl groups; but also higher alkyl groups containing from 8 to 20 carbon atoms, for example octyl, decyl, dodecyl, pentadecyl and octadecyl; as well as a phenyl and lower alkyl-phenyl group, such as

  
as tolyl or xylyl, and further a phenyl-lower alkyl group, such as benzyl or phenethyl.

  
Among the compounds covered by general formula I,

  
5 particularly important groups of compounds can be

  
 <EMI ID = 37.1>

  
following:

  

 <EMI ID = 38.1>


  
 <EMI ID = 39.1>

  
alkyl or cycloalkenyl which may be substituted by lower alkyl, lower alkoxy, hydroxy or oxo, optionally ketalised;

  

 <EMI ID = 40.1>
 

  
 <EMI ID = 41.1>

  
lower alkyl, lower alkoxy, hydroxy or [except for the phenyl group] an optionally ketalised oxo group;

  

 <EMI ID = 42.1>


  
 <EMI ID = 43.1>

  
or a lower alkyl group, and a = 1, b = 1, c = 1,

  
 <EMI ID = 44.1>

  
a = 0, b = 0, c = 0, the members a, b, c being optionally substituted by a hydroxy and / or lower alkoxy group, and the dotted bonds represent an optional C-C bond;

  
0

  
 <EMI ID = 45.1>

  
d

  
(0)

  

 <EMI ID = 46.1>


  
wherein ring A may be wholly or partially unsaturated, ring B partially unsaturated, and X represents a lower alkyl group Y represents a hydrogen atom or a lower alkyl group and Z a hydroxy, oxo, alkoxy or acyloxy.

  
The necessary starting compounds of general formula II

  
It <EMI ID = 47.1>

  
ID and IE can be represented. general following:

  

 <EMI ID = 48.1>


  
 <EMI ID = 49.1>

  
as above.

  
Examples include, among others:

  
1-ethynyl-cyclohexanol,

  
1-ethynyl-2,6,6-trimethyl-cyclohexanol and

  
 <EMI ID = 50.1>

  
cyclohex-2-ene &#65533;

  
u

  

 <EMI ID = 51.1>


  
in which R "2 has the same meaning as above.

  
This formula covers, for example, 3-hydroxy-3-phenylprop-1-yne;

  

 <EMI ID = 52.1>


  
 <EMI ID = 53.1>

  
or a lower alkyl group and the symbols a, b and c and the dotted bonds have the same

  
meaning as above.

  
 <EMI ID = 54.1>

  

 <EMI ID = 55.1>


  
where d has the same meaning as above.

  
Examples include, among others:

  
5- (2,6,6-trimethyl-cyclohex-1-en-1-yl) -3-hydroxy-3-

  
 <EMI ID = 56.1>

  
9- (4,4-ethylenedioxy-2,6,6-trimethyl-cyclohex-1-en-1yl) -3-hydroxy-3,7-dimethyl-nona-4,6,8-trien-1-yne ;

  

 <EMI ID = 57.1>


  
where X, Y and Z have the same meaning as above and ring A can be fully or <EMI ID = 58.1>

  
i

  
According to the process of the invention, the following compounds can be prepared in a particularly advantageous manner:

  
senecioic aldehyde (Prenal),

  
3-methyl-pent-2-en-1-al,

  
3,7-dimethyl-4-ethyl-octa-2,6-dien-1-al, non-2-en-1-al,

  
Citral,

  
7- (hydroxy or methoxy) -citral,

  
Farnesal,

  
Phytal,

  
cyclohexylidene-acetaldehyde

  
2,6,6-trimethyl-cyclohexylidene-acetic aldehyde, cinnamic aldehyde,

  
 <EMI ID = 59.1>

  
vitamin A aldehyde,

  
2-methyl-hept-2-en-4-one,

  
2,5-dimethyl-hex-2-en-4-one,

  
17- (formylmethylene) -androst-5-en-3P-ol,

  
 <EMI ID = 60.1>

  
3-methoxy-19-nor-prégna-1,3,5 (10), 17 (20) -tetraen-21-al.

  
Among the catalysts of the invention of general formula

  
 <EMI ID = 61.1>

  
general formula
 <EMI ID = 62.1>
  <EMI ID = 63.1>

  
cycloalkyl, phenyl or phenyl-lower alkyl,

  
are preferred. As representative examples of compounds of general formula IIIaa, there may be mentioned:

  
tris- [trimethyl-siloxy] -vanadium oxide,

  
tris- [tricyclohexyl-siloxy] -vanadium oxide and tris- [triphenyl-siloxy] -vanadium oxide.

  
The compounds of general formula IIIe, in which

  
n = 0 and B represents a sulfone group, can be prepared for example by a process characterized in that reacting 4-hydroxy-3-methyl-but-2-en-1-al or acetate or

  
the bromide of this alcohol in a polar solvent, for example in isopropanol or n-butanol, as (. 'written above, with the sulfinic acid described above or with an alkali metal salt of this acid .

  
Metalliphic silicon compounds of general formulas IIIa and IIIaa are known compounds. They can be prepared according to known methods, for example
-by reaction, for example, of vanadium pentoxide, <EMI ID = 64.1>

  
azeotrope of the water liberated during the reaction by means of an entraining agent such as benzene;
- by reaction, for example, of trichlorovanadium, <EMI ID = 65.1>

  
presence of a base such as pyridine or ammonia;
- by reaction, for example, of trichlorovanadium, for example with a trialkyl- [or triphenyl] -silanolate <EMI ID = 66.1> <EMI ID = 67.1> trialkyl- [or triphenyl] -silanol, optionally in the presence of catalytic amounts of an alkali alkyl or phenyl-silanolate, for example an alkali trialkyl-silanolate;
- by reaction, for example, of a siloxy oxide- <EMI ID = 68.1>

  
a trialkyl-silanol or a triphenyl-silanol in the presence of a catalytic amount of an alkali silanolate such as a tri- (lower alkyl) -silanolate alkali;
- By reaction, for example, of silver orthovanadate of general formula Ag3V04, for example with a trialkyl [or triphenyl) -silyl halide of general formula <EMI ID = 69.1>

  
benzene or methylene chloride;
- by reaction, for example, of vanadine pentoxide, for example with a hexa-alkyldisiloxane of general formula <EMI ID = 70.1>

  
at around 100 [deg.] or finally also
- by double reaction of a vanadic acid ester of <EMI ID = 71.1>

  
[or triphenylj-silyl, for example tripropyl orthovanadate with trimethylsilyl acetate with elimination of propyl acetate.

  
 <EMI ID = 72.1>

  
for the isomerization according to the invention, the silicon compounds of general formula
 <EMI ID = 73.1>
  <EMI ID = 74.1>

  
electrons are preferred.

  
By electron withdrawing groups is meant especially the groups mentioned by Fieser and Fieser in

  
 <EMI ID = 75.1>

  

 <EMI ID = 76.1>


  
As examples of catalysts of the invention of general formulas IIIb and IIIbb, there may be mentioned:
- tris- [tri- (p-fluorophenyl) -siloxy] -vanadium oxide
-tris- [tri- (p-chlorophenyl) -siloxy] -vanadium oxide
-tris- [tri- (p-bromophenyl) -siloxy] -vanadium oxide
- tris- [tri- (a, a, a-trifluoro-m-tolyl) -siloxy] vanadium oxide
- tris- [tri- (a, a, a-trifluoro-p-tolyl) siloxy] -vanadium oxide
- tris- [bis- (3-nitro-4-bromophenyl) - (4-bromophenyl) -siloxy] -vanadium oxide
- (tri-p-fluorophenyl) -siloxy-bis (triphenylsiloxy) -vanadium oxide
- tris- [tri- (4-biphenylyl) -siloxy] -vanadium oxide
- bis [tri- (p-fluorophenyl) -siloxy] triphenyl-siloxy-vanadium oxide <EMI ID = 77.1>

  
The catalysts of general formulas III, IIIb and IIIbr are new and can be prepared according to known methods, for example
- by reaction of vanadium pentoxide with an <EMI ID = 78.1>

  
KW "represents a phenyl radical substituted by one or more electron withdrawing groups] under azeotropic elimination of the water liberated during the reaction by means of an entraining agent such as benzene;
- By reaction of trichlorovanadium oxide with a silanol of general formula KW "SiOH [in which KW" represents a phenyl group substituted with one or more electron withdrawing groups] in the presence of a base such as pyridine or ammonia;
- by reaction of trichlorovanadium oxide with an <EMI ID = 79.1>

  
 <EMI ID = 80.1>

  
substituted with one or more electron withdrawing groups] in an inert solvent, such as diethyl ether;
- by reaction of a vanadic acid ester of <EMI ID = 81.1>

  
of general formula KW "SiOH [in which KW" represents a phenyl group substituted by a

  
or more electron withdrawing groups] optionally in the presence of catalytic amounts of an alkali alkyl- or phenylsilanolate, for example an alkali trialkylsilanolate; <EMI ID = 82.1> <EMI ID = 83.1>

  
KW "represents a phenyl group substituted by one or more electron withdrawing groups], optionally in the presence of catalytic amounts of an alkali silanolate, such as a tri- (lower alkyl) -silanolate alkali;
- by reaction of silver orthovanadate of formula <EMI ID = 84.1>

  
 <EMI ID = 85.1>

  
has a phenyl group substituted by one or more electron withdrawing groups and hal represents a halogen atom] in a solvent such as, for example, benzene or methylene chloride;
- by double reaction of a vanadic acid ester <EMI ID = 86.1>

  
[in which KW "represents a phenyl radical substituted by one or more electron withdrawing groups] for example tripropyl orthovanadate, with triphenyl-silyl acetate under elimination of propyl acetate, advantageously in a solvent such as as n-heptane, wherein the resulting ester forms an azeotrope separable from the reaction mixture.

  
Among the silanols of general formula IVb, the silanols of general formula
 <EMI ID = 87.1>
 <EMI ID = 88.1>

  
above,

  
are preferred.

  
Examples include, among others:

  
triphenylsilanol and

  
tricyclohexylsilanol.

  
Among the silanols of general formula IVa, the silanols of general formula

  

 <EMI ID = 89.1>


  
where KW "has the same meaning as above,

  
are preferred.

  
Examples include, among others:

  
tri- (p-fluorophenyl) -silanol,

  
tri- (p-chlorophenyl) -silanol,

  
tri- (p-bromophenyl) -silanol, <EMI ID = 90.1>

  
The catalytic isomerization according to the invention of acetylenecarbinols of general formula II into oxo a, &#65533; -nonsaturated compounds of general formula I is advantageously carried out by long heating of the corresponding carbinol with

  
the catalyst of general formula III after addition of a silanol of general formula IV. We use about 0.1

  
at 5 moles /% [preferably about 1.5 to 2 mole%]

  
of catalyst of general formula III relative to the substrate.

  
The silanol of general formula IV is added to the reaction mixture in an amount of approximately 0.01 mole% up to an amount in which it acts as a solvent. An amount of silanol between 1 and 85 mole%, especially 5 and 65 moles

  
is preferred. The amount of silanol used is based on

  
the substrate weight.

  
On the other hand, if the amount of silanol of general formula IV used is calculated relative to the amount of catalyst of general formula III present in the reaction mixture, the addition of silanol represents approximately 0.05 to 85,000 times

  
the molar amount of the catalyst employed. We use in

  
Generally about 5000 to 65000 times the molar amount of silanol, especially 5000 to 8500 times or 2500 to 8500 times the molar amount of silanol.

  
During isomerization, it is possible either to treat the substrate of general formula II with the catalytic system (composed of the catalyst of general formula III and of a silanol of general formula IV] or to proceed in reverse.

  
Isomerization can be carried out in a solvent

  
inert and in the presence or absence of air.

  
As suitable solvents, there may be mentioned, for example

  
aliphatic hydrocarbons such as heptane, cyclo-

J

  
 <EMI ID = 91.1> benzene, nitrobenzene, toluene, or xylene; halogenated hydrocarbons such as chlorobenzene; ethers such as anisol or dioxane, or also amines such as N-methylaniline. Mention may also be made of polymeric solvents with a silicon content, such as silicone oils containing aliphatic or aromatic radicals, for example methyl-phenyl-polysiloxanes.

  
As has already been said, the reaction mixture can also be treated with an excess of silanol of general formula IV. In this case, the silanol acts as a solvent.

  
The reaction temperature to be observed may be between approximately room temperature and 150 [deg.], Advantageously between approximately 40 and 110 [deg.].

  
If necessary, isomerization can also be carried out.

  
carried out under pressure, for example up to about 50 at.

  
The reaction time can vary within wide limits. It usually lasts about 2 to 20 hours.

  
The catalyst used keeps almost all of its sound

  
activity during isomerization. It can therefore

  
be used for several subsequent isomerizations [around 100-200] before being replaced.

  
The reaction product is separated in the usual way, for example by rectification of the unreacted parts of the carbinol used. The unreacted carbinol parts can be reused in the next load. According to this process, in general, results are obtained.

  
 <EMI ID = 92.1>

  
the starting material used.

  
 <EMI ID = 93.1>

  
 <EMI ID = 94.1>

  
15.2 g of dehydrolinalool, 1.1 g of tris- (triphenyl-siloxy) -vanadium oxide, 6.5 g of tri- (p-fluorophenyl) silanol and 100 ml of high-strength paraffin oil. ebul-

  
 <EMI ID = 95.1>

  
at 115 [deg.] under nitrogen. The reaction mixture is then cooled to 70 [deg.] And subjected, at this temperature, first to simple distillation, then to vacuum distillation.

  
(0.1 Torr.). During the last 30 minutes of distillation, the temperature is again raised to 140 [deg.] So that all the volatile parts redistillate. The residual catalyst / paraffin oil mixture can, as described above, be used again for the isomerization of 15.2 g feeds of dehydrolinalool. The results of

  
10 isomerizations carried out with the same catalyst are as follows:
- Dehydrolinalool conversion rate used: 93%
- Citral yield relative to the converted dehydrolinalool: 96%.

Example 2

  
15.2 g of dehydrolinalool, 1.4 g of tris- (tri-

  
 <EMI ID = 96.1>

  
and 180 ml high boiling paraffin oil

  
 <EMI ID = 97.1>

  
 <EMI ID = 98.1>

  
Citral yield relative to converted dehydrolinalool: 93%

  
The same catalyst can be used for many other isomerizations.

  
 <EMI ID = 99.1>

  
15.2 g of dehydrolinalool, 2.1 g of tris- (triphenyl-siloxy) -vanadium oxide, 4.5 g of tri- (p-bromophenyl) -silanol and 200 ml of high point paraffin oil boiling

  
 <EMI ID = 100.1>

  
- Yield of citral relative to the converted dehydrolinalool: 88%.

Example 4

  
 <EMI ID = 101.1>

  
of triphenylsilanol and 31.3 g of dehydrolinalol are mixed with stirring and heated to 110 [deg.] under an atmosphere of air or

  
inert gas. The resulting clear slightly yellowish solution after addition of 5.6 g of tris- (tri-
(a, a, a-trifluoro-m-tolyl) -siloxy] -vanadium is stirred for 6 hours at 105-110 [deg.]. The reaction mixture is then cooled to about 80 [deg.] And distilled under reduced pressure,
(0.1-0.5 Torr.). The citral which turns at 50-60 [deg.] / 1 Torr., Is completely distilled. Towards the end of the distillation,

  
the temperature is raised to about 140 [deg.] for about

  
15 minutes.

  
After removal of the citral, a further isomerization can be carried out immediately by treatment, as described above, of the residual paraffin oil / catalyst mixture, again at 110 [deg.] With 31.3 g of dehydrolinalool.

  
- Average yield of citral relative to the converted dehydrolinalool, over 50 isomerizations: 88.6%.

  
 <EMI ID = 102.1>

  
vanadium used as catalyst in Example 4 can for example be prepared as follows:

  
 <EMI ID = 103.1>

  
 <EMI ID = 104.1>

  
the solution is treated with 0.115 g of tris- (trimethyl-siloxy) -vanadium oxide. The mixture is brought to a boil

  
under reflux for 1 hour. 20 ml of benzene are first distilled with the resulting trimethylsilanol, at normal pressure, then 20 ml of benzene-toluene mixture are distilled again at normal pressure, after addition of 20 ml of toluene.

  
The toluene solution is concentrated under reduced pressure

  
at 50 [deg.]. Tris- [tri- (a, a, a-trifluoro-mtolyl) -siloxy] -vanadium oxide [molar peak: 1504] is obtained.

  
In a similar way we can prepare:

  
from tris- (trimethylsiloxy) -vanadium oxide

  
and tris- (a, a, a-trifluoro-p-tolyl) -silanol

  
Tris- [tri- (a, a, a-trifluoro-p-tolyl) -siloxy] - oxide

  
vanadium [molar peak = 1504];

  
from tris- (trimethylsiloxy) -vanadium oxide,

  
tris- (p-fluorophenyl) -silanol

  
and triphenylsilanol in a molar ratio of 1: 1: 2

  
(Tri-p-fluorophenyl) -siloxy-bis- (tri-

  
phenylsiloxy) -vanadium; melting point 2030;

  
from tris- (trimethylsiloxy) -vanadium oxide,

  
tris- (p-fluorophenyl) -silanol

  
and triphenylsilanol in a molar ratio of 1: 2: 1

  
 <EMI ID = 105.1>

  
triphenylsiloxy-vanadium, [molar peak = 1000];

  
from tris- (trimethylsiloxy) -vanadium oxide,

  
tris- (p-bromophenyl) -silanol

  
and cyclohexanol in a molar ratio of 1: 2: 1, bis- [tri- (p-bromophenyl) -siloxy] - oxide.

  
cyclohexyloxy-vanadium [peak corresponding to the

  
 <EMI ID = 106.1>

AT

  
 <EMI ID = 107.1>

  
Tris- [bis- (3-nitro-4-bromophenyl) oxide

  
(4-bromophenyl) -siloxy] -vanadium [peak corresponding to the molecular mass = 1873 measured on the basis of 79Br].

Example 5

  
10 g of 3-methyl-but-1-yn-3-ol and 8 g of triphenylsilanol

  
 <EMI ID = 108.1>

  
 <EMI ID = 109.1>

  
with 7.5 g of tris- [bis- (3-nitro-4-bromophenyl) oxide -
(4-bromophenyl) -siloxy] -vanadium. The reaction mixture

  
is cooled to about 78 [deg.] and distilled under reduced pressure, lowered to 5 Torr., towards the end of the distillation. There is thus obtained Prenal [3-methyl-but-2-en-1-al], p.éb. 132-133 [deg.] / 730 Torr.

  
The residual mixture composed of the paraffin oil employed, tris- [bis- (3-nitro-4-bromophenyl) - (4bromophenyl) -siloxy] -vanadium oxide and triphenylsilanol can

  
again be used for the isomerization of fillers

  
120 g of 3-methyl-but-1-yn-3-ol.

  
- Average yield of prenal over 20 isomerizations relative to reacted 3-methyl-but-l-yn-3-ol: 93.4%

Example 6

  
In a manner analogous to that of Example 3, one can isomerize:

  
3-methyl-pent-1-yn-3-ol

  
in 3-methyl-pent-2-en-1-al

  
boiling point 60 [deg.] / 35 Torr. Efficiency: 85%

  
1 ..

  
 <EMI ID = 110.1>

  
boiling point: 72 [deg.] / 0.4 Torr. Yield: 78.6%

  
3- [4 (or 3) -methyl-cyclohex-3-en-1-yl] -but-1-yn-3-ol in 3- [4 (or 3) -methyl-cyclohex-3-en- l-yl] -but-2-en-l-al

  
boiling point: 60 [deg.] / 0.3 Torr. Efficiency: 88.5%

  
3,7-dimethyl-7-methoxy-oct-1-yn-3-ol

  
3,7-dimethyl-7-methoxy-oct-2-en-1-al

  
boiling point: 66 [deg.] / 0.1 Torr. Yield: 84.2%

  
2,6-dimethyl-oct-7-yne-2,6-diol

  
[7-hydroxidehydrolinalol]

  
 <EMI ID = 111.1>

  
[7-hydroxycitral]

  
boiling point: 98 [deg.] / 0.3 Torr. Efficiency: 64.5%

  
1-ethynyl-cyclohexanol

  
in a) cyclohexylidene-acetaldehyde

  
boiling point: 48 [deg.] / 1.3 Torr. Yield: 46.5%

  
and in b) cyclohex-1-en-1-yl-acetaldehyde

  
boiling point 48 [deg.] / 1.3 Torr. Efficiency: 14%

  
l-ethynyl-2,6,6-trimethylcyclohexanol

  
in a) 2,2,6-trimethyl-cyclohexylidene-acetaldehyde

  
boiling point: 59 [deg.] / 0.6 Torr. Yield 12.5%

  
anden b) 2,2,6-trimethyl-cyclohex-1-en-1-yl-acetaldehyde

  
boiling point: 500 / 0.1 Torr. Efficiency: 74.5%

  
1-ethynyl-cyclopentanol

  
in cyclopentylidene-acetaldehyde <EMI ID = 112.1>

  
 <EMI ID = 113.1>

  
in non-2-en-l-al

  
boiling point: 34 [deg.] / 0.25 Torr. - Yield: 38%

  
2,5-dimethyl-hex-3-yn-2,5-diol

  
2,5-dimethyl-hex-2-en-5-ol-4-one

  
boiling point: 35 [deg.] / 0.2 Torr. Yield: 79.2%

  
 <EMI ID = 114.1>

  
[dehydronerolidol]

  
3,7,11-trimethyl-dodeca-2,6,10-trien-1-al

  
[farnesal]

  
boiling point: 86 [deg.] / 0.2 Torr. Yield: 91.6%

  
 <EMI ID = 115.1>

  
[dehydrogeranyllinalol]

  
in 3,7,11,15-tetramethyl-hexadeca-2,6,10,14-tetraen-1-al

  
[geranylcitralJ

  
boiling point: 135 [deg.] / 0.2 Torr. Yield: 71.5%

  
3,7,11,15-tetramethyl-hexadec-1-yn-3-ol

  
 <EMI ID = 116.1>

  
[phytal]

  
boiling point: 150 [deg.] / 0.3 Torr. Yield 75.8%.

Example 7

  
A mixture of 15.2 g of 3-hydroxy-3,7-dimethyl-octa6-en-1-yne (dehydrolinalool), 0.52 g of tris- [tri- (pbromophenyl) -siloxy] -vanadium oxide , 5.5 g of triphenylsilanol and
200 g of liquid paraffin [boiling point 170 [deg.] / 0.1 Torr.] Are heated at 100 [deg.] For 15 hours under inert gas. The citral formed is separated by rectification of the unconverted dehydrolinalool.

  
 <EMI ID = 117.1>

  
 <EMI ID = 118.1>

  
With the same catalyst, 40 cycles of isomerization of dehydrolinalool to citral can be carried out with a similar yield.

Example 8

  
15.2 g of dehydrolinalool, 0.8 g of tris- [tri-

  
 <EMI ID = 119.1>

  
silanol are heated at 120 [deg.] for 5 hours in 300 ml

  
silicone oil. The yield of citral relative to the converted dehydrolinalool is 92.5%.

  
After distillation of the volatile parts, the isomerization to citral can be repeated several times after

  
a further addition of dehydrolinalool.

Example 9

  
15.2 g of dehydrolinalool, 1.4 g of tris- [tri- (a, a, atrifluoro-p-tolyl) -siloxy] -vanadium, 4.8 g of tri- (p-tolyl) - silanol and 180 ml high boiling paraffin oil

  
 <EMI ID = 120.1>

  
5 hours.

  
The yield of citral relative to the converted dehydrolinalool is 94.2%.

  
The same catalyst can be used for many isomerizations.

  
 <EMI ID = 121.1>

  
15.2 g of dehydrolinalool, 2.1 g of tris- [tri-
(4-biphenylyl) -siloxy] -vanadium, 4.5 g of tris- (m-tolyl) -sllanol and 200 ml of high boiling paraffin oil

  
 <EMI ID = 122.1>

  
Citral yield compared to dehydrolinalool

  
 <EMI ID = 123.1>

Example 11

  
15.2 g of dehydrolinalool, 2.45 g of tris- (pfluorophenyl) -siloxy-vanadium oxide, 1.8 g of dicyclohexyl-methylsilanol and 90 ml of high-boiling paraffin oil

  
 <EMI ID = 124.1>

  
under anhydrous conditions.

  
The yield of citral relative to the unconverted dehydrolinalool is 86.4%.

Example 12

  
13.2 g of 3-hydroxy-3-phenyl-prop-1-yne, 3.2 g of bis- [tri- (p-fluorophenyl) -siloxy] - [triphenyl-siloxy] vanadium oxide, 4, 51 g of triphenylsilanol and 100 ml of silicone oil are heated for 8 hours at 115 [deg.] Under anhydrous conditions.

  
The yield of cinnamic aldehyde is 87.6%.

Example 13

  
1.04 g of 3-methoxy-19-nor-prégna-1,3,5 (10) -trien-20-yn- <EMI ID = 125.1>

  
20 ml of xylene are heated for 6 hours at 120 [deg.]. After cooling, the reaction solution is diluted with hexane, filtered and concentrated. 3-methoxy-19-nor-

  
 <EMI ID = 126.1>

  
at 141-155 [deg.] (0.746 g) after redistillation from hexane and recrystallization from isopropanol.

Example 14

  
15.2 g of dehydrolinalool, 1.2 g of tris- [tri-
(p-fluorophenyl) -siloxy] -vanadium, 6.5 g of tri- (p-fluorophenyl) silanol and 100 ml of high-boiling paraffin oil

  
 <EMI ID = 127.1>

  
under nitrogen. The mixture is then cooled to 70 [deg.] And first subjected at this temperature to a simple distillation then

  
vacuum distillation (pressure: 0.1 Torr.). In

  
the last 30 minutes of the distillation process, we

  
allow the temperature to rise to 140 [deg.] in order to distill off all the volatile parts. The catalyst / residual paraffin oil mixture can be used again for further isomerizations.

  
- Average yield of citral over 10 isomerizations: 96%.

  
The tris- [tri- (p-fluorophenyl) -siloxy] -vanadium oxide used in Example 14 can for example be prepared as follows:

  
1 g of tris- (p-fluorophenyl) -silanol is dissolved in

  
30 ml of absolute benzene. The solution is processed in

  
 <EMI ID = 128.1>

  
of trichlorovanadium oxide. The mixture is stirred first

  
for 8 hours at room temperature and then brought to reflux temperature for 2 hours. The pyridinium hydrochloride which precipitates after cooling to 10 [deg.] Is

  
separated by filtration. The filtrate is concentrated under pressure

AT

  
 <EMI ID = 129.1>

  
n-heptane.

  
In an analogous way, we can prepare:

  
from trichloro-vanadium oxide

  
and tris- (p-chlorophenyl) -silanol (m.p. 127-128 [deg.])

  
 <EMI ID = 130.1>

  
vanadium; melting point 181 [deg.];

  
from trichloro-vanadium oxide

  
and tris- (p-bromophenyl) -silanol (m.p. 120-121 [deg.]) tris- [tri- (p-bromophenyl) -siloxy] - oxide

  
vanadium; melting point 175 [deg.];

  
from trichloro-vanadium oxide

  
and tris-4-biphenylyl-silanol (mp 199-200 [deg.])

  
Tris- [tri- (4-biphenylyl) -siloxy] - oxide

  
vanadium.


    

Claims (1)

<EMI ID = 131.1> 1. Process for the preparation of oxo compounds of general formula <EMI ID = 132.1> <EMI ID = 133.1> <EMI ID = 134.1> alkyl or alkenyl which may be bonded with a cycloalkyl, cycloalkenyl or phenyl radical, or a radical <EMI ID = 135.1> can form a cycloalkyl or cycloalkenyl radical, which in turn can be condensed with one or more cycloalkyl or cycloalkenyl radicals; and R3 represents a hydrogen atom or an alkyl or alkenyl radical which may be bonded with a cycloalkyl, cycloalkenyl or phenyl radical, or a cycloalkyl, cycloalkenyl or phenyl radical; the alkyl, alkenyl, cycloalkyl, cycloalkenyl and phenyl radicals mentioned being optionally substituted by lower alkyl, lower alkoxy, hydroxy, lower alkanoyl, aroyl, lower alkanoyloxy or aroyloxy, or [except for the phenyl group] by an oxo group or oxo ketalized, by catalytic isomerization of a tertiary carbinol of general formula <EMI ID = 136.1> <EMI ID = 137.1> <EMI ID = 138.1> <EMI ID = 139.1> characterized in that the isomerization is carried out with a catalyst of general formula <EMI ID = 140.1> <EMI ID = 141.1> from the series of lower alkyl, cycloalkyl, phenyl or phenyl-lower alkyl, the phenyl radical possibly being substituted by one or more electron withdrawing groups, R represents a <EMI ID = 142.1> n = 0, 1 or 2, and m + n = 3, and a silanol of general formula <EMI ID = 143.1> <EMI ID = 144.1> as above, the catalyst of general formula III and / or the silanol of general formula IV having at least one phenyl radical containing one or more electron withdrawing groups. 2. Method according to claim 1, characterized in that the isomerization is carried out with a catalyst of general formula <EMI ID = 145.1> in which m and n have the same meaning as <EMI ID = 146.1> from the series of lower alkyl, cycloalkyl, phenyl or phenyl-lower alkyl, R 'represents <EMI ID = 147.1> and a silanol of general formula <EMI ID = 148.1> in which m and n have the same meaning as <EMI ID = 149.1> owned by one or more attracting groups <EMI ID = 150.1> 3. Method according to claim 1, characterized in that the isomerization is carried out with a catalyst of general formula <EMI ID = 151.1> <EMI ID = 152.1> tion as above, with a silanol of general formula <EMI ID = 153.1> where m, n and YW, have the same meaning as above. 4. Method according to claim 1, characterized in that the isomerization is carried out with a catalyst of general formula <EMI ID = 154.1> in which m, n, KW "and R" have the same meaning as above, and a silanol of general formula <EMI ID = 155.1> he <EMI ID = 156.1> cation than above. 5. Method according to claim 2, characterized in that tris- (triphenyl-siloxy) vanadium oxide is used as a catalyst and tri- (p-fluoro [or p-chloro or p-bromo] phenyl) -silanol as silanol. 6. Method according to claim 3, characterized in <EMI ID = 157.1> <EMI ID = 158.1> triphenylsilanol as silanol. 7. The method of claim 4, characterized in that the oxide of tris- [tri- (p-fluoro [or p-chloro or p-bromo] -phenyl) -siloxy] -vanadium is used as catalyst and tri- (p-fluoro [or p-chloro or p-bromo] -phenyl) -silanol as silanol. 8. Method according to one of claims 1 to 7, characterized in that the isomerization is carried out in a solvent. 9. Process according to Claim 8, characterized in that the isomerization is carried out in a hydrocarbon, in particular 1! Paraffin oil. 10. The method of claim 8, characterized in that the isomerization is carried out in a silicone oil, in particular methyl-phenyl-polysiloxane. 11. Method according to one of claims 1 to 10, characterized in that the isomerization is carried out in a temperature range between room temperature and the boiling point of the reaction mixture. 12. Method according to one of claims 1 to 11, characterized in that a carbinol of general formula is used. <EMI ID = 159.1> in which R "2 represents a cycloalkyl, cycloalkenyl or phenyl radical which may be substituted by lower alkyl, lower alkoxy, <EMI ID = 160.1> as the starting compound. 13. The method of claim 12, characterized in that 3-hydroxy-3-phenyl-prop-1-yne is used as the starting substance. 14. Method according to one of claims 1 to 11, characterized in that one uses as starting compound a carbinol of general formula <EMI ID = 161.1> <EMI ID = 162.1> a lower alkyl group, and a = 1, b = 1, c = 1 <EMI ID = 163.1> a = 0, b = 0, c = 0, the members a, b, c being optionally substituted by a hydroxy and / or lower alkoxy group, and the dotted bonds represent an optional C-C bond. 15. The method of claim 14, characterized in that 3-hydroxy-3-methyl-but-1-yne is used as the starting compound. 16. The method of claim 14, characterized in that 3-hydroxy-3,7-dimethyl-octa-6-en-1-yne is used as the starting compound. 17. The method of claim 14, characterized in what is used 3-hydroxY-3,7,11-trimethyl-dodeca-6,10-dien- <EMI ID = 164.1> <EMI ID = 165.1> 6,10,14-trien-1-yne as the starting compound. <EMI ID = 166.1> characterized in that a carbinol of general formula is used as starting compound <EMI ID = 167.1> in which ring A can be wholly or partially unsaturated, ring B partially unsaturated, and X represents a lower alkyl group, Y a hydrogen atom or a lower alkyl group and Z a hydroxy, oxo, alkoxy group or acyloxy. 20. The method of claim 19, characterized in that 3-methoxy-19-nor-prégna-1,3,5 (10) trien-20-yn-17-ol is used as the starting compound.