A catalyst for preparing an enol from an alkyne alcohol, a method for preparing the same, and a method for preparing an enol

Abstract

The application provides a catalyst for preparing an enol from an alkyne alcohol, a preparation method and a method for preparing the enol by using the catalyst. By precisely controlling the particle size, specific surface area and added toxicant of the Lindlar catalyst, the catalytic efficiency can be significantly improved, and the catalyst performance is quantified with each parameter, so that the catalyst can be widely applied in industrial production.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of organic chemical synthesis, in particular to a catalyst for preparing enol from alkyne alcohol, a preparation method thereof, and a method for preparing enol from partial hydrogenation of alkyne alcohol by using the catalyst. BACKGROUND

[0002] Enol is a main intermediate for producing vitamin E, and is also an intermediate or product for synthesizing vitamin A, vitamin K1, carotenoids, linalool and some other flavor varieties. In the field of organic chemical synthesis, the preparation of enol from hydrogenation of alkyne alcohol is an important reaction, which is widely used in the fields of pharmaceuticals, fine chemicals and the like. The traditional method for hydrogenation of alkyne alcohol mainly uses metal catalysts such as palladium and platinum, but these catalysts are expensive, and the degree of hydrogenation reaction is difficult to control, so it is difficult to control alkyne alcohol at the stage of enol. Therefore, it is of great research value to find an efficient and low-cost method for hydrogenation of alkyne alcohol.

[0003] In order to solve the above problems, researchers began to explore new catalysts and reaction conditions. Among them, Lindlar catalyst is a commonly used catalyst for hydrogenation of alkyne alcohol, which has good catalytic activity and stability. This type of catalyst is to precipitate metal palladium on a carrier such as barium sulfate or calcium carbonate, and then treat it with lead acetate or quinoline to poison and reduce the catalytic activity of palladium, so that the hydrogenation reaction of alkyne alcohol stays at the stage of enol. However, early researchers found that the catalyst was easy to be poisoned and deactivated, and the selective hydrogenation was also difficult to control. In order to improve the selectivity of hydrogenation, it is necessary to control the content of over-hydrogenation products, and the basic principle is to reduce the activity of the catalyst.

[0004] The catalytic efficiency of Lindlar catalyst is affected by its physical properties such as particle size and specific surface area. Therefore, researchers have improved the catalytic efficiency of Lindlar catalyst by changing its physical properties. In patent CN201380032718, the particle size of the calcium carbonate carrier is controlled to be more than 10 μm to improve the proportion of enol. However, the patent does not give the quantitative relationship between the particle size, specific surface area and other factors of the catalyst and the performance of the catalyst, and the change of the reaction conditions and the performance of the catalyst are not mentioned, so it is difficult to form a regular and universal standard to guide production practice.

[0005] A more general principle is to add sulfur and nitrogen compounds to reduce the activity of the catalyst, and common compounds include quinoline, pyridine, mercaptans and the like. The selection principle can be considered as an application of the poisoning of Lindlar catalyst. When the catalyst is poisoned, the activity of the catalyst is inhibited, so that the alkyne cannot be completely converted into alkane, but into alkene. However, there is still a problem that the poisoning component and the catalytic effect are difficult to be quantified. SUMMARY

[0006] To solve the above technical problems existing in the prior art, the application provides a catalyst for preparing an enol from an alkyne alcohol, the catalytic efficiency of which is significantly improved by quantifying the performance of the catalyst and various parameters, so that the process of preparing the enol from the alkyne alcohol is more efficient, and the catalyst is particularly suitable for guiding industrial production.

[0007] Another object of the application is to provide a preparation method of the catalyst for preparing an enol from an alkyne alcohol.

[0008] Still another object of the application is to provide a method for preparing an enol from an alkyne alcohol by using the catalyst for preparing an enol from an alkyne alcohol.

[0009] To achieve the above objects, the application adopts the following technical solutions.

[0010] The catalyst for preparing an enol from an alkyne alcohol is a Lindlar catalyst modified by a poisoning agent, and the performance parameter A of the Lindlar catalyst modified by the poisoning agent meets the following formula:

[0011]

[0012] In which:

[0013] A is the performance parameter of the catalyst, and the unit is 1;

[0014] S is the specific surface area of the catalyst, and the unit is m 2 / g;

[0015] C Pd is the mass percentage content of palladium in the Lindlar catalyst;

[0016] C Pb is the mass percentage content of lead in the Lindlar catalyst;

[0017] C Zn is the total content of zinc, iron, copper, magnesium, aluminum and cobalt ions in the hydrogenation reaction solution for preparing the enol from the alkyne alcohol, and the unit is ppm;

[0018] C N is the total content of nitrogen, phosphorus and sulfur ions in the hydrogenation reaction solution for preparing the enol from the alkyne alcohol, and the unit is ppm;

[0019] Φ is the particle size of the catalyst, represented by the average particle size d 50 , and the unit is μm;

[0020] In addition, the absolute value of A-1 is less than or equal to 1.2, and preferably less than or equal to 0.6.

[0021] In some specific embodiments, the average particle size d 50 of the Lindlar catalyst is 1-30 μm, and preferably 5-20 μm; and the specific surface area is 0.5-10 m 2 / g, preferably 1-5 m 2 / g.

[0022] In some specific embodiments, the Lindlar catalyst is a noble metal catalyst supported on a carrier;

[0023] Preferably, the supported noble metal is palladium, and the carrier is barium sulfate or calcium carbonate, preferably calcium carbonate;

[0024] More preferably, the mass content of the supported palladium metal is 1%-25%, preferably 2%-10%, based on the total mass of the Lindlar catalyst.

[0025] In some specific embodiments, the Lindlar catalyst is pre-poisoned with lead acetate, and the mass content of the pre-poisoned lead is 0%-20%, preferably 2%-10%, based on the total mass of the Lindlar catalyst.

[0026] In some specific embodiments, the poisoning agent is at least one of a metal salt, a metal carbonyl compound, a nitrogen-, phosphorus- or sulfur-containing compound, and the metal is selected from Group VIII, Group IB or Group IIB elements, preferably any one of zinc, iron, copper, magnesium, aluminum, cobalt;

[0027] In some specific embodiments, the nitrogen-, phosphorus- or sulfur-containing compound is selected from any one of a mercaptan, an organic amine, an inorganic ammonium, an organic phosphine, preferably any one of methyl mercaptan, triphenyl phosphine, triphenyl phosphine oxide, ammonia, ammonium phosphate.

[0028] Preferably, the metal salt or metal carbonyl compound is selected from any one of zinc acetate, ferrous acetate, iron pentacarbonyl, tririron dodecacarbonyl or dicobalt octacarbonyl, preferably zinc acetate or tririron dodecacarbonyl.

[0029] In some specific embodiments, the total amount of the poisoning agent added is 0.01-100 ppm of the total content of zinc, iron, copper, magnesium, aluminum, cobalt ions in the hydrogenation reaction liquid;

[0030] Preferably, the total content of nitrogen, phosphorus, sulfur ions in the hydrogenation reaction liquid is 0.01-50 ppm.

[0031] In another aspect, the aforementioned method for preparing a catalyst for preparing an enol from an alkyne alcohol comprises the following steps:

[0032] 1) preparing a Lindlar catalyst precursor meeting the particle size requirement;

[0033] 2) supporting and reducing noble metal on the Lindlar catalyst precursor, and then modifying by poisoning with a poisoning agent.

[0034] In still another aspect, a method for preparing an enol from an alkyne alcohol, the method comprising using an alkyne alcohol having the general structure I as a substrate, and subjecting the substrate to a partial hydrogenation reaction in the presence of a catalyst for preparing an enol from an alkyne alcohol to form an enol having the general structure II:

[0035]

[0036] wherein R1 and R2 are hydrogen or a hydrocarbon group, preferably a branched or straight-chain C6-C 20 alkyl or alkenyl group, and more preferably, one of R1 or R2 is hydrogen and the other is a branched or straight-chain C6-C 20 alkyl or alkenyl group;

[0037] Preferably, the alkyne alcohol is selected from any one of 2-methyl-3-buten-2-ol, dehydro-linalool, dihydro-dehydro-linalool, dehydro-neral, dihydro-dehydro-neral, tetrahydro-dehydro-neral, or dehydro-isophytol.

[0038] More preferably, the catalyst for preparing an enol from an alkyne alcohol is added in an amount of 0.1% to 20% of the mass of the alkyne alcohol, and preferably in an amount of 0.5% to 2% of the mass of the alkyne alcohol.

[0039] In some specific embodiments, during the reaction, hydrogen is introduced to maintain a pressure of 0.1 MPa to 3.0 MPa (absolute pressure), and preferably a pressure of 0.2 MPa to 1.0 MPa (absolute pressure); the reaction temperature is 0°C to 90°C, and preferably 20°C to 60°C; and the reaction time is 0.1 h to 24 h, and preferably 0.5 h to 12 h.

[0040] In some specific embodiments, the partial hydrogenation reaction is carried out in a solvent environment, and after the reaction is completed, the catalyst is separated from the solvent.

[0041] Preferably, the solvent is selected from one or more of pure water, an inert aliphatic alkane that does not react with the raw material, an aromatic hydrocarbon, an ether, and an alcohol, and preferably is selected from one or more of pure water, n-heptane, toluene, and ethanol.

[0042] Compared with the prior art, the present application has the following positive effects:

[0043] The present application improves the catalytic efficiency of the Lindlar catalyst by modifying the catalyst system with a poisoning agent and by controlling the particle size and specific surface area of the Lindlar catalyst and the content of the poisoning agent to satisfy a specific relationship, so that the process for preparing an enol from an alkyne alcohol is more efficient. Furthermore, by quantifying the performance of the catalyst and various parameters, the present application is particularly suitable for guiding industrial production. DETAILED DESCRIPTION

[0044] The following examples will further illustrate the process provided by the present application, but the present application is not limited to the listed examples, and any other known modifications within the scope of the claimed rights of the present application should also be included.

[0045] A catalyst for preparing alkenols from alkynols, the catalyst is a Lindlar catalyst modified by a poisoning agent, the performance parameter A of the Lindlar catalyst modified by the poisoning agent meets the following formula:

[0046]

[0047] Wherein:

[0048] A is the catalyst performance parameter, unit is 1;

[0049] S is the specific surface area of the catalyst, unit m 2 / g;

[0050] C Pd is the mass percentage content of palladium in the Lindlar catalyst;

[0051] C Pb is the mass percentage content of lead in the Lindlar catalyst;

[0052] C Zn is the total content of zinc, iron, copper, magnesium, aluminum, cobalt ions in the hydrogenation reaction solution for preparing alkenols from alkynols, unit ppm;

[0053] C N is the total content of nitrogen, phosphorus, sulfur ions in the hydrogenation reaction solution for preparing alkenols from alkynols, unit ppm;

[0054] Φ is the particle size of the catalyst, represented by the average particle size d 50 , unit μm;

[0055] And the absolute value of A-1 is less than or equal to 1.2, for example, 1.2, 1.1, 1.0, 0.9, 0.8, 0.7, 0.6, 0.5, 0.4, 0.3, 0.2, 0.1, 0, etc., preferably less than or equal to 0.6.

[0056] In the present application, the Lindlar catalyst is a commonly used catalyst in the field of preparing alkenols from alkynols, for example, it is usually that metallic palladium is precipitated on a carrier such as barium sulfate or calcium carbonate, and then treated with lead acetate or quinoline poisoning. Specific Lindlar catalysts can be directly purchased from the market, for example, Lindlar catalyst CAS: 7440-05-3 of Xi'an Kailixin Material Co., Ltd., or self-made by existing public technology.

[0057] In the present application, by precisely controlling the particle size of the Lindlar catalyst to be 1-30 μm, such as 1 μm, 3 μm, 5 μm, 7 μm, 9 μm, 10 μm, 12 μm, 15 μm, 18 μm, 20 μm, 23 μm, 25 μm, 27 μm, 30 μm, etc., preferably 5-20 μm; and the specific surface area to be 0.5-10 m 2 / g, such as 0.5 m 2 / g, 1 m 2 / g, 2 m 2 / g, 3 m 2 / g, 4 m 2 / g, 5 m 2 / g, 6 m 2 / g, 7 m 2 / g, 8 m 2 / g, 9 m 2 / g, 10 m 2 / g, etc., preferably 1-5 m 2 / g, the catalytic efficiency of the catalyst can be significantly improved, and the process of preparing alkenyl alcohol by hydrogenation of alkynyl alcohol is more efficient. The particle size of the catalyst refers to the average particle size d 50 .

[0058] Generally, the particle size of the Lindlar catalyst on the market is 20-100 microns, and the specific surface area is 3-10 m 2 / g, and the particle size and specific surface area can be adjusted within a certain range, for example, the particle size and specific surface area of the catalyst can be adjusted to the target range by the method of ball milling with a ball mill. The specific operation is as follows: the precursor of the Lindlar catalyst (i.e. the Lindlar catalyst carrier not meeting the particle size and specific surface area of the present application) is put into the ball mill, the rotation speed is set to 50-1000 r / min, such as 100 r / min, 200 r / min, 300 r / min, 400 r / min, 500 r / min, 600 r / min, 700 r / min, 800 r / min, 900 r / min, etc., and the grinding time is 0.1-48 h, such as 0.1 h, 0.5 h, 0.8 h, 1 h, 2 h, 3 h, 4 h, 5 h, 6 h, 7 h, 8 h, 9 h, 10 h, 11 h, 12 h, 15 h, 18 h, 20 h, 22 h, 24 h, etc., to obtain the Lindlar catalyst carrier with the desired particle size and specific surface area. The preparation operation of the Lindlar catalyst can refer to the master's degree thesis of Zhejiang University, "Study on the selective hydrogenation of methyl butynyl alcohol", and the catalyst is prepared by the equal-volume impregnation method or the impregnation reduction method.

[0059] The Lindlar catalyst described in the present application, the supported noble metal is preferably palladium, the carrier is barium sulfate or calcium carbonate, preferably calcium carbonate; the mass content of palladium metal loaded in the Lindlar catalyst is in the range of 1% to 25%, for example 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 12%, 15%, 17%, 19%, 20%, 22%, 24%, 25%, etc., preferably 2% to 10%. The Lindlar catalyst is usually pre-poisoned with lead acetate, and the mass content of lead is in the range of 0% to 20%, for example 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 12%, 15%, 17%, 19%, 20%, etc., preferably 2% to 10%.

[0060] In the present application, the hydrogenation reaction solution of acetylene alcohol to prepare enol is the hydrogenation reaction system of acetylene alcohol to prepare enol, except that the catalyst is not dissolved in the reaction system, the others can be dissolved in the system, because the amount of the poisoning agent added is very small, the total amount of the solvent and acetylene alcohol can basically represent the total amount of the hydrogenation reaction solution of acetylene alcohol to prepare enol, that is, the amount of the hydrogenation reaction solution can be approximately equal to the total amount of the solvent and acetylene alcohol.

[0061] In another aspect of the present application, the preparation method of the aforementioned catalyst for preparing enol from acetylene alcohol comprises the following steps:

[0062] 1) Prepare a Lindlar catalyst precursor (or carrier) meeting the particle size requirements;

[0063] 2) Load and reduce noble metal on the Lindlar catalyst precursor (or carrier), and then modify it with a poisoning agent.

[0064] Among them, the Lindlar catalyst precursor (or carrier) meeting the particle size requirements is prepared or obtained first, and then noble metal is loaded and reduced, and then a poisoning agent is added for modification. Among them, the Lindlar catalyst precursor meeting the particle size requirements can be obtained by grinding the Lindlar catalyst precursor (or carrier) with a large particle size and specific surface area to obtain a catalyst precursor with a target particle size and specific surface area, and then loading palladium by impregnation or the like, and then modifying it with a poisoning agent.

[0065] The added poisoning agent is at least one of a metal salt or a metal carbonyl compound, a compound containing nitrogen, phosphorus or sulfur, and the metal is selected from group VIII, group IB or group IIB elements, preferably zinc, iron, copper, magnesium, aluminum, cobalt. Further preferably, the metal salt or metal carbonyl compound is selected from zinc acetate, ferrous acetate, pentacarbonyl iron, dodecacarbonyl triiron or octacarbonyl dicobalt, etc., and more preferably zinc acetate or dodecacarbonyl triiron.

[0066] The total addition amount of the poisoning agent in the preparation method is 0.01-100 ppm, for example, 0.02 ppm, 0.05 ppm, 0.1 ppm, 0.5 ppm, 0.8 ppm, 1 ppm, 5 ppm, 8 ppm, 10 ppm, 15 ppm, 20 ppm, 25 ppm, 30 ppm, 35 ppm, 40 ppm, 45 ppm, 50 ppm, 55 ppm, 60 ppm, 65 ppm, 70 ppm, 75 ppm, 80 ppm, 85 ppm, 90 ppm, 95 ppm, 100 ppm, etc. of the total content of zinc, iron, copper, magnesium, aluminum and cobalt ions in the reaction solution. The nitrogen, phosphorus and sulfur ions in the reaction solution also have a poisoning effect on the catalyst. The nitrogen, phosphorus and sulfur ions can be actively added or passively introduced. The nitrogen, phosphorus and sulfur ions can be introduced by a compound containing nitrogen, phosphorus and sulfur, i.e. a compound containing nitrogen, a compound containing phosphorus, a compound containing sulfur, or a compound containing any two or more of nitrogen, phosphorus and sulfur, for example, any one of mercaptans, organic amines, inorganic ammonium, organic phosphines, etc. For example, methyl mercaptan, triphenyl phosphine, triphenyl phosphine oxide, ammonia, ammonium phosphate, etc. The total content thereof should be controlled to be 0.01-50 ppm, for example, 0.02 ppm, 0.05 ppm, 0.1 ppm, 0.5 ppm, 0.8 ppm, 1 ppm, 5 ppm, 8 ppm, 10 ppm, 15 ppm, 20 ppm, 25 ppm, 30 ppm, 35 ppm, 40 ppm, 45 ppm, 50 ppm, etc. of the reaction solution. The total content of nitrogen, phosphorus and sulfur ions should not be too high to avoid excessive poisoning of the catalyst activity.

[0067] In still another aspect of the present application, the present application also provides a method for preparing an enol by partially hydrogenating an acetylene alcohol using the above-mentioned catalyst. The acetylene alcohol having the general structure I is used as a substrate. The enol having the general structure II is formed by the partial hydrogenation reaction under the action of the above-mentioned catalyst for preparing an enol by partially hydrogenating an acetylene alcohol:

[0068]

[0069] wherein R1 and R2 are hydrogen or a hydrocarbon group, preferably a branched or straight-chain C6-C 20 alkyl or alkenyl group. More preferably, one of R1 or R2 is hydrogen and the other is a branched or straight-chain C6-C 20 alkyl or alkenyl group. More preferably, one of R1 or R2 is hydrogen and the other is a branched or straight-chain C6-C 20 alkyl or alkenyl group. More preferably, one of R1 or R2 is hydrogen and the other is a branched or straight-chain C6-C

[0070] The acetylenic alcohol in the method of the present application is preferably selected from 2-methyl-3-butyne-2-ol, dehydro-linalool, dihydro-dehydro-linalool, dehydro-nerolidol, dihydro-dehydro-nerolidol, tetrahydro-dehydro-nerolidol, dehydro-isophytol and the like, the corresponding molecular structures of which are as follows:

[0071]

[0072] The catalyst used in the method of the present application for the partial hydrogenation of the acetylenic alcohol to produce the enolic alcohol is used in an amount of 0.1% to 20% by mass of the acetylenic alcohol, for example 0.1%, 0.5%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 12%, 15%, 17%, 19%, 20% and the like, preferably 0.5% to 2%.

[0073] The hydrogen pressure during the partial hydrogenation reaction in the method of the present application is 0.1 MPa to 3.0 MPa (absolute pressure), for example 0.1 MPa, 0.2 MPa, 0.5 MPa, 0.8 MPa, 1 MPa, 1.5 MPa, 2 MPa, 2.5 MPa, 2.8 MPa, 3 MPa and the like, preferably 0.2 MPa to 1.0 MPa (absolute pressure).

[0074] The reaction temperature during the reaction in the method of the present application is 0 to 90°C, for example 2°C, 5°C, 10°C, 20°C, 30°C, 40°C, 50°C, 60°C, 70°C, 80°C, 90°C and the like, preferably 20 to 60°C; and the reaction time is 0.1 h to 24 h, for example 0.1 h, 0.5 h, 0.8 h, 1 h, 2 h, 3 h, 4 h, 5 h, 6 h, 7 h, 8 h, 9 h, 10 h, 11 h, 12 h, 15 h, 18 h, 20 h, 22 h, 24 h and the like, preferably 0.5 h to 12 h.

[0075] The reaction in the method of the present application is carried out in a solvent environment, and after the reaction is completed, the catalyst is separated from the solvent. The solvent is selected from one or more of pure water, an inert aliphatic alkane that does not react with the starting material, an aromatic hydrocarbon, an ether, an alcohol and the like, for example one or more of pure water, n-heptane, toluene, ethanol and the like.

[0076] The conversion of the acetylenic alcohol in the method of the present application is ≥ 99.0%, the selectivity of the enolic alcohol is ≥ 98.0%, and the selectivity of the over-hydrogenated product is < 1.0%.

[0077] The present application is further explained by more specific examples below, but without any limiting effect.

[0078] The analytical methods used in the following examples are as follows:

[0079] Gas chromatograph: Agilent 7820A, column HP-5 (30 m x 320 pm x 0.25 pm), injection port temperature: 150 °C; split ratio 50:1; carrier gas flow: 1.5 ml / min; temperature program: 40 °C for 1 min, ramped to 90 °C at 10 °C / min, held for 0 min, then ramped to 160 °C at 5 °C / min, held for 0 min, then ramped to 280 °C at 30 °C / min, held for 6 min. Detector temperature: 280 °C.

[0080] The raw materials referred to in the following examples are as follows:

[0081] Lindlar catalyst - 5% Pd - 5% Pb, specific surface area 1.26 m 2 / g, d50 = 6.77 pm, Jiangsu Xinnuo Catalyst Co., Ltd;

[0082] Lindlar catalyst - 5% Pd - 10% Pb specific surface area 1.13 m 2 / g, d50 = 15.31 pm, Jiangsu Xinnuo Catalyst Co., Ltd;

[0083] Lindlar catalyst - 2% Pd - 2% Pb specific surface area 4.13 m 2 / g, d50 = 3.65 pm, Jiangsu Xinnuo Catalyst Co., Ltd;

[0084] Lindlar catalyst - 5% Pd - 0% Pb, specific surface area 1.56 m 2 / g, average particle size d50 = 5.21 pm, Xi'an Kailixin Materials Co., Ltd

[0085] Lindlar catalyst - 10% Pd - 20% Pb, specific surface area 2.61 m 2 / g, average particle size d50 = 7.82 pm, Xi'an Kailixin Materials Co., Ltd

[0086] Zinc acetate, 99%, Shanghai Aldrin Biochemical Technology Co., Ltd;

[0087] Iron acetate, 99%, Shanghai Aldrin Biochemical Technology Co., Ltd;

[0088] Dicobalt octacarbonyl, 97%, Shanghai Aldrin Biochemical Technology Co., Ltd;

[0089] Triphenylphosphine, 99%, Shanghai Aldrin Biochemical Technology Co., Ltd;

[0090] Dehydroisoaromadendrol, 98%, InoKai Technology Co., Ltd;

[0091] Dehydrolinalool, 98%, Innovay Technology Co., Ltd.;

[0092] 2-Methyl-3-butyn-2-ol, 99%, Innovay Technology Co., Ltd.;

[0093] Dehydro-orange-flower-ol, 97%, Innovay Technology Co., Ltd.;

[0094] Example 1

[0095] First, add ethanol 100 g, 5% Pd-5% Pb palladium-calcium carbonate catalyst 1.5 g, Lindlar catalyst specific surface area 1.26 m 2 / g, catalyst particle size with average particle size d50 of 6.77 μm, add zinc acetate 50 ppm, add triphenylphosphine 20 ppm, calculate Add dehydrolinalool 294.5 g to the autoclave, seal the autoclave, replace with nitrogen for 6 times, then replace with hydrogen for 6 times, start the stirring paddle, keep the hydrogen pressure at 1.0 MPa (gauge pressure), keep the temperature in the reactor at 60℃, react for 8 h. Stop stirring and vent the gas, then analyze the reaction liquid by GC, the conversion rate of acetylenic alcohol is 99.8%, the selectivity of enolic alcohol is 98.7%, and the selectivity of over-hydrogenated product is 0.3%.

[0096] Example 2

[0097] First, add ethanol 100 g, 5% Pd-10% Pb palladium-calcium carbonate catalyst 1.0 g, Lindlar catalyst specific surface area 1.13 m 2 / g, catalyst particle size with average particle size d50 of 15.31 μm, add zinc acetate 70 ppm, add triphenylphosphine 30 ppm, calculate Add dehydrolinalool 294.5 g to the autoclave, seal the autoclave, replace with nitrogen for 6 times, then replace with hydrogen for 6 times, start the stirring paddle, keep the hydrogen pressure at 3.0 MPa (gauge pressure), keep the temperature in the reactor at 30℃, react for 12 h. Stop stirring and vent the gas, then analyze the reaction liquid by GC, the conversion rate of acetylenic alcohol is 35.6%, the selectivity of enolic alcohol is 95.2%, and the selectivity of over-hydrogenated product is 2.5%.

[0098] Example 3

[0099] Prepare enolic alcohol according to the method of Example 2, except that no zinc acetate is added during the reaction, calculate 152.1 g of dehydrolinalool was added to the autoclave, which was then sealed. The autoclave was purged with nitrogen six times, followed by hydrogen purging six times. The stirrer was turned on, and the hydrogen pressure was maintained at 0.5 MPa (gauge pressure). The temperature inside the autoclave was kept at 80°C, and the reaction was carried out for 4 hours. After stirring was stopped and the air was vented, the reaction solution was analyzed by GC. The alkynyl alcohol conversion rate was 49.2%, the enol selectivity was 96.1%, and the selectivity of the over-hydrogenation product was 2.1%.

[0100] Example 4

[0101] First, add 100g of methanol, 8.0g of 2% Pd-2% Pb palladium-calcium carbonate catalyst, and a Lindela catalyst with a specific surface area of ​​4.13m² to the autoclave. 2 / g, catalyst particle size with an average particle size d50 of 3.65μm, zinc acetate 90ppm added, triphenylphosphine 40ppm added, calculate 84.6 g of 2-methyl-3-butyn-2-ol was added to a high-pressure reactor. The reactor was sealed, and the mixture was purged with nitrogen six times, followed by hydrogen six times. The stirrer was turned on, and the hydrogen pressure was maintained at 2.0 MPa (gauge pressure). The reactor temperature was kept at 50 °C, and the reaction was carried out for 2 hours. After stirring was stopped and the air was vented, the reaction solution was analyzed by GC. The alkynol conversion rate was 99.5%, the enol selectivity was 96.1%, and the selectivity of the over-hydrogenation product was 1.7%.

[0102] Example 5

[0103] First, add 100g of n-hexane, 4.0g of 10% Pd-20% Pb palladium-calcium carbonate catalyst, and a Lindela catalyst with a specific surface area of ​​2.61m² to the autoclave. 2 / g, catalyst particle size with an average particle size d50 of 7.82μm, 200ppm of octacarbonyl dicobalt added, 10ppm of methanethiol added, calculate 220.1 g of dehydronerol was added to the autoclave, which was then sealed. The autoclave was purged with nitrogen six times, followed by hydrogen purging six times. The stirrer was turned on, and the hydrogen pressure was maintained at 0.2 MPa (gauge pressure). The temperature inside the autoclave was kept at 70°C, and the reaction was carried out for 24 hours. After stirring was stopped and the air was vented, the reaction solution was analyzed by GC. The alkynol conversion rate was 97.6%, the enol selectivity was 93.1%, and the selectivity of the over-hydrogenation product was 4.1%.

[0104] Example 6

[0105] First, add 100g of toluene, 2.0g of 5% Pd-0% Pb palladium-calcium carbonate catalyst, and a Lindela catalyst with a specific surface area of ​​1.56m² to the autoclave. 2 / g, catalyst particle size with an average particle size d50 of 5.21μm, 85ppm ferric acetate added, 30ppm ammonia added, calculate To the autoclave was added dehydrolinalool 152.1 g, the autoclave was sealed, replaced with nitrogen 6 times and then replaced with hydrogen 6 times, the stirring paddle was turned on, the hydrogen pressure was maintained at 0.5 MPa (gauge pressure), the temperature in the reactor was maintained at 80 °C, and the reaction was run for 4 h. After the stirring was stopped and the gases were vented, the reaction mixture was analyzed by GC, the alkyne alcohol conversion was 98.9%, the enol selectivity was 97.1%, and the over-hydrogenated product selectivity was 1.3%.

[0106] Comparative Example 1

[0107] The enol was prepared according to the procedure of Reference Example 6, except that the amount of iron acetate added during the reaction was changed from 85 ppm to 50 ppm, calculated as Fe. To the autoclave was added dehydrolinalool 152.1 g, the autoclave was sealed, replaced with nitrogen 6 times and then replaced with hydrogen 6 times, the stirring paddle was turned on, the hydrogen pressure was maintained at 0.5 MPa (gauge pressure), the temperature in the reactor was maintained at 80 °C, and the reaction was run for 4 h. After the stirring was stopped and the gases were vented, the reaction mixture was analyzed by GC, the alkyne alcohol conversion was 98.9%, the enol selectivity was 97.1%, and the over-hydrogenated product selectivity was 1.3%.

[0108] Comparative Example 2

[0109] The enol was prepared according to the procedure of Reference Example 3, except that the catalyst used in Reference Example 4, 2% Pd-2% Pb on calcium carbonate catalyst, Lindlar catalyst, was used, having a specific surface area of 4.13 m2 / g, and a catalyst particle size of 3.65 μm average particle size d50, calculated. 2 To the autoclave was added 2-methyl-3-butyne-2-ol 84.6 g, the autoclave was sealed, replaced with nitrogen 6 times and then replaced with hydrogen 6 times, the stirring paddle was turned on, the hydrogen pressure was maintained at 2.0 MPa (gauge pressure), the temperature in the reactor was maintained at 50 °C, and the reaction was run for 2 h. After the stirring was stopped and the gases were vented, the reaction mixture was analyzed by GC, the alkyne alcohol conversion was 99.5%, the enol selectivity was 8.2%, and the over-hydrogenated product selectivity was 85.1%.

[0110] Comparative Example 3

[0111] The enol was prepared according to the procedure of Reference Example 4, except that no zinc acetate and triphenylphosphine were added during the reaction, calculated as Zn and P. To the autoclave was added 2-methyl-3-butyne-2-ol 84.6 g, the autoclave was sealed, replaced with nitrogen 6 times and then replaced with hydrogen 6 times, the stirring paddle was turned on, the hydrogen pressure was maintained at 2.0 MPa (gauge pressure), the temperature in the reactor was maintained at 50 °C, and the reaction was run for 2 h. After the stirring was stopped and the gases were vented, the reaction mixture was analyzed by GC, the alkyne alcohol conversion was 99.5%, the enol selectivity was 8.2%, and the over-hydrogenated product selectivity was 85.1%.​

Claims

1. A catalyst for the preparation of an enol from an alkyne alcohol, characterized in that, The catalyst is a Lindlar catalyst modified by a poisoning agent, and the performance parameter A of the Lindlar catalyst modified by the poisoning agent meets the following formula: Wherein: A is the catalyst performance parameter, and the unit is 1; S is the catalyst specific surface area in m 2 / g; C Pd is the mass percent content of palladium in the Lindlar catalyst; C Pb is the mass percentage content of lead in the Lindlar catalyst; C Zn Total content of zinc, iron, copper, magnesium, aluminum, cobalt ions in the hydrogenation reaction solution for preparing enol from alkynol, unit: ppm; C N Total content of nitrogen, phosphorus and sulfur ions in the hydrogenation reaction solution for preparing enol from acetylene alcohol, unit: ppm; Φ is the catalyst particle size, in average particle size d 50 indicates, in units of μm; And the absolute value of A-1 is less than or equal to 1.

2.

2. The catalyst for preparing an enol from an alkyne alcohol according to claim 1, characterized by, The absolute value of A-1 is less than or equal to 0.

6.

3. The catalyst for the preparation of an enol from an alkyne alcohol according to claim 1 or 2, characterized in that The average particle size d of the Lindela catalyst 50 Its thickness is 1-30 μm; its specific surface area is 0.5-10 m². 2 / g.

4. The catalyst for preparing an enol from an alkyne alcohol according to claim 3, characterized by, The average particle size d of the Lindela catalyst 50 The thickness is 5-20 μm; the specific surface area is 1-5 m². 2 / g.

5. The catalyst for preparing an enol from an alkyne alcohol according to claim 1 or 2, characterized by, The Lindlar catalyst is a noble metal catalyst supported on a carrier.

6. The catalyst for preparing an enol from an alkyne alcohol according to claim 5, wherein The supported noble metal is palladium, and the carrier is barium sulfate or calcium carbonate.

7. The catalyst for preparing an enol from an alkyne alcohol according to claim 6, characterized by, The carrier is calcium carbonate.

8. The catalyst for preparing an enol from an alkyne alcohol according to claim 6, wherein The mass content of the supported palladium metal is 1%-25% based on the total mass of the Lindlar catalyst.

9. The catalyst for preparing an enol from an alkyne alcohol according to claim 8, characterized by, The mass content of the supported palladium metal is 2%-10%.

10. The catalyst for preparing an enol from an alkyne alcohol according to claim 1 or 2, characterized by, The Lindlar catalyst is pre-poisoned by lead acetate, and the mass content of the pre-poisoned lead is 1%-20% based on the total mass of the Lindlar catalyst.

11. The catalyst for preparing an enol from an alkyne alcohol according to claim 10, characterized by, The mass content of the pre-poisoned lead is 2%-10%.

12. The catalyst for the preparation of an enol from an alkyne alcohol according to claim 1 or 2, characterized in that, The poisoning agent is at least one of a metal salt, a metal carbonyl compound, and a compound containing nitrogen, phosphorus or sulfur, and the metal is selected from Group VIII, Group IB or Group IIB elements.

13. The catalyst for preparing an enol from an alkyne alcohol according to claim 12, characterized by, The metal is any one of zinc, iron, copper, magnesium, aluminum, or cobalt.

14. The catalyst for preparing an enol from an alkyne alcohol according to claim 12, wherein The metal salt or metal carbonyl compound is any one of zinc acetate, ferrous acetate, pentacarbonyl iron, tridecacarbonyl iron, or dicobalt octacarbonyl.

15. The catalyst for preparing an enol from an alkyne alcohol according to claim 14, wherein The metal salt or metal carbonyl compound is zinc acetate or tridecacarbonyl iron.

16. The catalyst for preparing an enol from an alkyne alcohol according to claim 12, wherein The compound containing nitrogen, phosphorus or sulfur is any one of a mercaptan, an organic amine, an inorganic ammonium, or an organic phosphine.

17. The catalyst for preparing an enol from an alkyne alcohol according to claim 16, wherein The compound containing nitrogen, phosphorus or sulfur is any one of methyl mercaptan, triphenyl phosphine, triphenyl phosphine oxide, ammonia, or ammonium phosphate.

18. The catalyst for preparing an enol from an alkyne alcohol according to claim 12, wherein The total content of zinc, iron, copper, magnesium, aluminum, and cobalt ions in the hydrogenation reaction liquid is 0.01-100 ppm.

19. The catalyst for preparing an enol from an alkyne alcohol according to claim 18, wherein The total content of nitrogen, phosphorus, and sulfur ions in the hydrogenation reaction liquid is 0.01-50 ppm.

20. A process for the preparation of a catalyst for the preparation of an enol from an alkyne alcohol according to any one of claims 1 to 19, characterized in that, It comprises the following steps: 1) Prepare a Lindlar catalyst carrier meeting the particle size requirements; 2) Load and reduce the Lindlar catalyst carrier with a noble metal, and then modify it with a poisoning agent.

21. A method of preparing an enol from an alkyne alcohol, characterized by, An alkenol with structural formula II is formed after partial hydrogenation reaction of an alkyne alcohol with structural formula I as the substrate under the action of the catalyst for preparing an alkenol from an alkyne alcohol according to any one of claims 1-19: Wherein, R1 and R2 are hydrogen or a hydrocarbon group.

22. The method of claim 21, wherein, R1, R2are branched or linear C6-C 20 alkyl or alkenyl groups.

23. The method of claim 22, wherein, one of R1or R2is hydrogen, the other is branched or straight chain C6-C 20 alkyl or alkenyl.

24. The method of claim 21, wherein, The alkyne alcohol is any one of 2-methyl-3-butyne-2-ol, dehydro-linalool, dihydro-dehydro-linalool, dehydro-neral, dihydro-dehydro-neral, tetrahydro-dehydro-neral, or dehydro-isophytol.

25. The method of claim 24, wherein, The catalyst for preparing an alkenol from an alkyne alcohol is added in an amount of 0.1%-20% of the mass of the alkyne alcohol.

26. The method of claim 25, wherein, The catalyst for preparing an alkyne alcohol from an alkyne alcohol is added in an amount of 0.5%-2% of the mass of the alkyne alcohol.

27. The method of claim 21, wherein, During the reaction, hydrogen is introduced to maintain a pressure of 0.1-3.0 MPa absolute pressure; the reaction temperature is 2-90°C; and the reaction time is 0.1-24 h.

28. The method of claim 27, wherein, During the reaction, hydrogen is introduced to maintain a pressure of 0.2-1.0 MPa absolute pressure; the reaction temperature is 20-60°C; and the reaction time is 0.5-12 h.

29. The method of any one of claims 21-28, wherein, The partial hydrogenation reaction is carried out in a solvent environment, and the catalyst is separated from the solvent after the reaction is completed.

30. The method of claim 29, wherein, The solvent is selected from one or more of pure water, an inert aliphatic alkane that does not react with the starting material, an aromatic hydrocarbon, an ether, an alcohol.

31. The method of claim 30, wherein, The solvent is one or more of pure water, n-heptane, toluene, ethanol.

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