CN106542983A - A kind of chiral 3,3,5 trimethylcyclohexanone（TMCH）Preparation method - Google Patents
A kind of chiral 3,3,5 trimethylcyclohexanone（TMCH）Preparation method Download PDFInfo
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- CN106542983A CN106542983A CN201610849493.5A CN201610849493A CN106542983A CN 106542983 A CN106542983 A CN 106542983A CN 201610849493 A CN201610849493 A CN 201610849493A CN 106542983 A CN106542983 A CN 106542983A
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- B01J31/02—Catalysts comprising hydrides, coordination complexes or organic compounds containing organic compounds or metal hydrides
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- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C45/00—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds
- C07C45/78—Separation; Purification; Stabilisation; Use of additives
- C07C45/85—Separation; Purification; Stabilisation; Use of additives by treatment giving rise to a chemical modification
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Abstract
The invention discloses one kind prepares chiral 3,3,5 trimethylcyclohexanone（TMCH）Catalyst and its corresponding preparation method, its preparation method is：3,3,5 trimethylcyclohexanone of racemic modification is obtained with hydrogen reaction in catalyst is directly added into solvent, and described catalyst is：Al after PEG stable nano Pd catalyst, roasting2O3Carrier and S proline.
Description
Technical field
The present invention relates to a kind of preparation method of chiral 3,3,5- trimethylcyclohexanones.
Background technology
As chipal compounds have special biologically active and excellent property, in the more than ten years in past, single chiral
The synthesis of compound has become the fast-developing key areas of Fine Chemical.
3,3,5- trimethylcyclohexanones（TMCH）It is the fine solvent of the coating such as resin, paint, varnish, its chiral enantiomer
(S-TMCH and R-TMCH) is the important intermediate of pharmacy, spices.TMCH mainly passes through isophorone at present（IP）C=C it is double
Key selective hydrogenation is obtained, but gained product TMCH is the mixture-racemic modification of S-TMCH and R-TMCH
TMCH, to obtain single chiral TMCH, is difficult to using physical method, and it is using hydrogenation power to study at present more
Learn the method for splitting.
To racemic modification 3,3,5- trimethylcyclohexanones（TMCH）Carrying out Kinetic Resolution has some research reports, to relevant
The research of reaction mechanism is not also fully aware of.At present, the gas-liquid-solid heterogeneous catalytic reaction body of Kinetic Resolution is carried out to TMCH
System, the optimization of the preparation method and reaction process condition of catalyst is the key for preparing high-purity chiral TMCH product problems.
The content of the invention
The technical problem to be solved is to propose that one kind prepares chiral 3,3,5- tri- for the above-mentioned state of the art
Methyl cyclohexanone（TMCH）Preparation method, obtain highly purified chiral 3 therefrom, 3,5- trimethylcyclohexanones（TMCH）.
The present invention solve the technical scheme that adopted of above-mentioned technical problem for：
Chiral 3,3,5- trimethylcyclohexanones（TMCH）Preparation method, it is characterised in that：Including first by PEG stable nano Pd particle
Catalyst dipping Al after baking2O3On carrier, then with S- proline, racemic modification 3,3,5- trimethylcyclohexanones add together
Obtain with hydrogen reaction in entering solvent.
Above-mentioned PEG stable nano Pd catalyst is obtained by following methods：Take palladium, PEG400, ethanol mixing, normal temperature
Lower ultrasound reduction is obtained.
The preferable reaction condition of above-mentioned hydrogenation reaction is：Temperature is 60-100 DEG C, and pressure is 1.0-2.0MPa, the reaction time
For 5-12h.
Above-mentioned best reaction condition is：Reaction temperature be 100 DEG C, pressure 1MPa, the reaction time be 8 h.
Compared with prior art, it is an advantage of the current invention that：As a result of new method for preparing catalyst and reaction
The hybrid mode of raw material, catalyst and dressing agent, has obtained highly purified chiral TMCH.
Racemic modification TMCH Kinetic Resolution reaction conditions are optimized, has obtained preparing the suitable of high-purity chiral TMCH
Reaction condition.
Description of the drawings
Fig. 1 is PEG-Pd ethanol solutions UV-vis figures under embodiment of the present invention difference ultrasonic time.
Specific embodiment
Below in conjunction with accompanying drawing embodiment, the invention will be further described.
The material and method of one embodiment
1 reaction raw materials
Palladium bichloride, (L)-Pro, ethanol are AR；The TMCH of Ti Xiai chemical conversion industries Development Co., Ltd production（99%+）；Cigarette
Boehmite of the trade mark of Tai Heng brightness company production for V250.
2 catalyst preparations
In following catalyst preparation process, raw material dosage is consistent, wherein palladium 0.0156g, PEG400 1g, ethanol 6g, S-
Proline 0.684g, 2.736g Al2O3。
The preparation of CA-1：Palladium, PEG400, ethanol mixing are taken, ultrasonic 50min obtains the stable nano Pd particles of PEG400
Catalyst.By Al2O3Carrier（Boehmite is in 500 DEG C of roasting 4h）It is added in the stable nano Pd catalysts of PEG400, stirs
20min is mixed, sealing preserve is well mixed.Made catalyst is directly added into high pressure with S- proline without milled processed during reaction
In kettle.This reaction system is designated as：Pd-Al2O3+Pro。
The preparation of CA-2：Palladium, PEG400, ethanol mixing are taken, ultrasonic 50min obtains the stable nano Pd particles of PEG400
Catalyst.By Al2O3Carrier（500 DEG C of roasting 4h）20min, and the nanometer that PEG400 is stable are ground in mortar with S- proline
Pd catalyst mixes, and stirs 20min, is well mixed.This reaction system is designated as：Pro-Al2O3-Pd。
The preparation of CA-3：Palladium, PEG400, ethanol mixing are taken, ultrasonic 50min obtains the stable nano Pd particles of PEG400
Catalyst.By Al2O3Carrier（500 DEG C of roasting 4h）It is added in the stable nano Pd catalysts of PEG400, stirs 20min, mixing
Uniformly, then it is vacuum dried.S- proline is ground into 20min with the catalyst, in autoclave being added during reaction.This reactant
System is designated as：Pd-Al2O3-Pro。
The preparation of CA-4：Palladium, PEG400, ethanol mixing are taken, ultrasonic 50min obtains the stable nano Pd particles of PEG400
Catalyst.By Al2O3Carrier（500 DEG C of roasting 4h）20min is ground with S- proline, is not impregnated, during reaction, is directly added into height
In pressure kettle.This reaction system is designated as：Pd+Pro-Al2O3。
The preparation of CA-5：Nano Pd particle, carrier and proline are added separately to.Palladium, PEG400, ethanol mixing are taken,
Ultrasonic 50min, obtains the stable nano Pd catalysts of PEG400.Do not impregnated, by Al2O3Carrier（500 DEG C of roasting 4h）、S-
Proline is directly added in autoclave when reacting.This reaction system is designated as：Pd+Pro+Al2O3。
The sign of 3 nano Pd catalysts
（1）UV-vis spectroscopy photometry（UV-vis）Analysis
SPECORD-205 type ultraviolet-visible spectrophotometers（Jena, Germany analytical technology limited company）For determining
Prepare the content of palladium in catalyst.
The preparation of 4 chirality TMCH
By CA-1,24g alcohol solvents, during 0.84gTMCH adds 100mL autoclaves, after leading to 1MPa hydrogen exchanges 4 times,
40 DEG C, react 5h under 1MPa hydrogen.Reaction cools after terminating, and kettle is driven in pressure release, and product Jing centrifugal treatings take upper organic phase
Quantitative analysis is carried out with chiral column in gas-chromatography.
CA-2, CA-3, CA-4, CA-5 experimental procedure is with CA-1 catalyst.
5 product analysis
Material in kettle after reaction is centrifuged, supernatant liquor is taken with dropper, using 6820 gas chromatographs of Agilent
The ee% values of analysis chirality TMCH.
Chromatographic condition：Beta-schardinger dextrin capillary column；Injection port carrier gas：He；Injector temperature：250℃；Post case temperature：From
50 DEG C with 5 DEG C/min temperature programmings to 220 DEG C, 34.47 kPa of column head pressure；Fid detector, 250 DEG C of temperature.
Enantiomeric excess value is calculated by following formula：
ee%=([S]-[R])/([R]+[S])×100
Wherein：The concentration of [S] for (S)-TMCH, the concentration of [R] for (R)-TMCH.
The result of implementation of two embodiments
1. impact of the ultrasound to Pd ion reductions
Weigh 0.0156g palladiums, 1gPEG400,6g ethanol to react under ultrasonication.At interval of 5min, UV- is carried out
Vis is analyzed, and recording solution color change, as a result sees Fig. 1 and Biao 1.
As seen from Figure 1, with the prolongation of ultrasonic reaction time, characteristic absorption peak of the divalent palladium near 400nm gradually subtracts
It is weak, show that divalent palladium is gradually reduced into zeroth order palladium.Additionally, as shown in table 1, with the prolongation of ultrasonic time, solution colour by
Gradually deepen, experience the change order of light yellow-orange-yellow-yellowish-brown-grey black, the change is likely due to nanoparticle palladium and is in
What different chemical environments was caused.In the process of ultrasound, palladium gradually dissolves, disperses, and is reduced into zeroth order palladium.In ultrasound
In the presence of, the zeroth order palladium particle being reduced out forms nano level dispersion, with the prolongation in reaction time, palladium concentration in system
It is stepped up, the optical property of nano-particle changes, causes the scattering to light different with absorption, so as to color progressively adds
It is deep.
Fig. 1 is also shown that the prolongation with ultrasonic time, and the characteristic absorption peak intensity at 400nm gradually weakens, meanwhile, base
Line substantially rises, and this is, as palladium nanoparticles are gradually formed and quantity increases, to cause ultraviolet light scattering to strengthen so that baseline
Rise, after ultrasonic 40min, baseline is basically unchanged, and shows that the reduction reaction of palladium has been basically completed.
Catalyst solution color change in 1 ultrasonic reduction process of table
| Time（min） | Color |
| 5 | It is light yellow |
| 10 | It is orange |
| 20 | Yellowish-brown |
| 30 | Celadon |
| 40 | Grey black |
| 50 | Grey black |
From the aforegoing it can be seen that suitable ultrasonic time is not less than 40min, most preferably 50min, so in following examples
50min is adopted.
2. the impact of nano Pd catalyst and chiral modifier load to preparation chirality TMCH.
Impact of 2 method for preparing catalyst of table to preparation chirality TMCH
Adopt racemic modification TMCH for reaction substrate, the results are shown in Table shown in 2 using what different catalyst was obtained.
As known from Table 2, in TMCH Dynamic Resolution process, S-TMCH and R-TMCH is carried out in the liquid phase with proline
Dehydrating condensation, as dehydrating condensation is long response time, in system, the presence of aluminum oxide has is carried out beneficial to the reaction, is produced in the middle of R-TMCH
The irreversibility of thing hydrogenation has broken the thermodynamical equilibrium of dehydration, promotes the conversion of R-TMCH, causes S-TMCH excess.
Conversion ratio, TMCH conversion ratios, S-TMCH yields and ee% from R-TMCH in general, is urged in racemic TMCH Kinetic Resolution
The order that the performance of agent system is descending is changed, and this is sequentially：Nano Pd particle list is loaded（Pd- Al2O3+Pro）>
It is individually added into（Pd+Pro+ Al2O3）>Proline list is loaded（Pro- Al2O3+Pd）>Pd rear bearing proline is carried first（Pd-
Al2O3-Pro）>Proline rear bearing Pd is carried first（Pro- Al2O3-Pd）.The result shows Dynamic Resolution process in TMCH
In, proline is that crucial rate determining step is rapid with the dehydration condensation of TMCH.Therefore, proline is individually added into more in alcohol solvent
Be conducive to the carrying out of dehydration condensation, and the nano Pd particle of hydrophilic carrier alumina load may be more beneficial in dehydrating condensation
Between product absorption and hydrogenation reaction, so as to be conducive to the conversion and fractionation of TMCH.
3. racemic modification TMCH prepares the reaction condition of chirality TMCH
（1）Reaction temperature
As shown in Table 3, with the rising of reaction temperature, two kinds of mapping transformation rates are presented elevated trend, simply transforming degree
It is different.Between 20 DEG C to 60 DEG C, the change of S-TMCH conversion ratios is little, and R-TMCH conversion ratios are substantially increased, and product ee% is dramatically increased.
60 DEG C are further added by temperature later, and although the conversion ratio of R-TMCH increased, but impact of the temperature to S-TMCH becomes apparent from,
And the conversion of R-TMCH is nearly completed after 80 DEG C, product ee% also increases seldom.High-temperature is risen within the specific limits, is had
Beneficial to the raising of palladium particle hydrogenation activity, be also beneficial to proline and the carrying out of dehydration be condensed with TMCH, two kinds of enantiomers
Conversion all accordingly can be improved.But the conversion of S-TMCH is more sensitive for high temperature, and this can cause the yield losses of S-TMCH.
Therefore, the suitable temperature of preparation chirality TMCH is：60-100 DEG C, consider S-TMCH yields and product ee%, most
Good reaction temperature is 100 DEG C.
The impact that 3 reaction temperature of table is reacted to TMCH Kinetic Resolutions
* other reaction conditions：Pressure 1MPa, time 5h.
（2）Reaction pressure
As shown in Table 4, as the conversion ratio of the rising of pressure, S-TMCH and R-TMCH is presented the trend of rising, product ee% values
First raise and be slightly decreased afterwards.In the range of 0.5 ~ 1.5MPa, the change of S-TMCH conversion ratios is little, and when reaching 2MPa, conversion ratio has
Improved.And after 1MPa, the change of R-TMCH conversion ratios is little, the transformation in planta rate of TMCH is to rise.It can be seen that S-TMCH
Conversion it is more sensitive for pressure, and the conversion of R-TMCH is easy for carrying out at low pressures.
Therefore, the convenient pressure of preparation chirality TMCH is：1-2MPa, considers S-TMCH yields and product ee%, most preferably
Reaction pressure is 1MPa.
The impact * that 4 Hydrogen Vapor Pressure of table is reacted to TMCH Kinetic Resolutions
* other reaction conditions：80 DEG C of temperature, time 5h
（3）Reaction time
As shown in Table 5, prolongation over time, two kinds of mapping transformation rates gradually increase, the ee% values of product in it is elevated become
Gesture.After 8h, the conversion of R-TMCH continues prolongation chronergy unobvious close to balance.And prolongation over time, S-TMCH
Conversion ratio gradually increases, and the ee% values of product are dramatically increased in 1-8 hours, are maintained at 86% or so after 8 hours.As purpose is produced
Thing is S-TMCH, and the prolongation time can cause its yield to reduce.
Therefore, the right times of preparation chirality TMCH are：5h-12h, considers S-TMCH yields and product ee%, most preferably
Reaction time is 8 hours.
The impact * that 5 Hydrogen Vapor Pressure of table is reacted to TMCH Kinetic Resolutions
* other reaction conditions：80 DEG C of temperature, pressure 1MPa.
In sum, TMCH Kinetic Resolutions optimum reaction condition is：100 °C, 1MPa, 8 hours, with optimal conditions,
Obtained by TMCH Kinetic Resolutions, chiral product S-TMCH ee% values reach 91.03%.
Claims (4)
1. chirality 3,3,5- trimethylcyclohexanones（TMCH）Preparation method, it is characterised in that：Including first by PEG stable nanometer
Pd catalyst dipping Al after baking2O3On carrier, then with S- proline, racemic modification 3,3,5- trimethylcyclohexanones are simultaneously
Obtain with hydrogen reaction in adding solvent.
2. chirality 3,3,5- trimethylcyclohexanones as claimed in claim 1（TMCH）Preparation method, it is characterised in that：It is described
PEG stable nano Pd catalyst is obtained by following methods：Take palladium, PEG400 to mix with ethanol, ultrasound reduction is obtained.
3. chirality 3,3,5- trimethylcyclohexanones as claimed in claim 1 or 2（TMCH）Preparation method, it is characterised in that：
The preferable reaction condition of hydrogenation reaction is：The temperature is 60-100 DEG C, and pressure is 1.0-2.0MPa, and the reaction time is 5-12h.
4. chirality 3,3,5- trimethylcyclohexanones as claimed in claim 3（TMCH）Preparation method, it is characterised in that：It is described
Reaction condition reaction temperature be 100 DEG C, 1 MPa of pressure, the reaction time be 8 h.
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| CN104984760A (en) * | 2015-05-07 | 2015-10-21 | 中国石油大学(华东) | Method for preparing (S)-3,3,5-trimethylcyclohexanone, and catalyst thereof |
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| CN104984760A (en) * | 2015-05-07 | 2015-10-21 | 中国石油大学(华东) | Method for preparing (S)-3,3,5-trimethylcyclohexanone, and catalyst thereof |
Non-Patent Citations (3)
| Title |
|---|
| JULIANE KEILITZ等: "Homogeneous Stabilization of Pt Nanoparticles in Dendritic Core–Multishell Architectures: Application in Catalytic Hydrogenation Reactions and Recycling", 《CHEMCATCHEM》 * |
| 王芳珠等: "单层分散(L)-脯氨酸修饰的Pd /Al2O3催化剂上3,3,5-三甲基环己酮的动力学拆分", 《精细化工》 * |
| 韩维: "合成4,4’-二氟二苯甲酮的绿色综合有机化学实验", 《广州化工》 * |
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