CN115745754A - Synthesis method of acetal - Google Patents

Abstract

The invention discloses a method for synthesizing acetal. In particular to olefin and H under the action of Rh/phosphine ligand complex and molecular sieve co-catalyst ₂ Application of a one-pot method for preparing acetal by heating CO and organic alcohol, belonging to the technical field of organic chemistry. The Rh/phosphine ligand complex and the molecular sieve cocatalyst provided by the invention are used in the series hydroformylation/acetalation reaction of olefin, and have high catalytic rate, substrate applicability and high regioselectivity.

Description

A kind of synthetic method of acetal

technical field

The present invention relates to a kind of synthetic method of acetal. Specifically, it relates to the application of a one-pot method for preparing acetal by heating olefin, CO/H ₂ and organic alcohol under the action of Rh/phosphine ligand complex and molecular sieve co-catalyst, and belongs to the technical field of organic chemistry.

technical background

The hydroformylation reaction refers to the process in which alkenes and CO/ _H2 generate aldehydes under the action of a catalyst. Olefin hydroformylation is an important method for industrial synthesis of aldehydes. Aldehydes are very valuable fine chemicals and important synthetic intermediates. In the further synthesis of aldehyde compounds, it is often necessary to protect the aldehyde group. Through the "hydroformylation-acetalization" cascade reaction of alkenes, the "one-pot" synthesis of alkenes functional groups to acetals can be achieved. The synthesized acetal groups are inert to oxidizing agents, reducing agents and alkalis. At the same time, the acetal group can be deprotected under acidic conditions to obtain the aldehyde group. This approach has important synthetic implications for olefinic substrates containing functional groups. Therefore, the "hydroformylation-acetalization" series reaction effectively avoids the process of separation and purification of aldehyde intermediates, and is more in line with the principles of green chemical atom economy and low energy consumption. Acetals are commonly used as solvents, fragrances, detergents or additives in oils and fuels, and to protect sensitive aldehyde groups from side reactions in organic synthesis. However, in the tandem hydroformylation-acetalization reaction of olefins currently developed, there are disadvantages such as low catalyst activity and poor selectivity of the target product. These problems limit the further industrial application of this reaction. Therefore, the development of highly active and highly selective catalytic systems has important academic and application value.

Contents of the invention

1. a synthetic method of acetal, it is characterized in that described method is: under the effect of Rh/phosphine ligand complex and molecular sieve co-catalyst as shown in general formula 1, alkene I, H ₂ /CO and Organic alcohol heating reaction; After the reaction is complete, centrifuge the molecular sieve, and obtain the acetal II shown in the general formula 1 through vacuum distillation;

R are independently selected from hydrogen, C ₁ -C ₁₀ alkane groups, C ₁ -C ₁₀ alkoxy groups,

wherein R ^x are independently selected from hydrogen, hydroxyl, sulfonic acid group, halogen, nitrile group, C ₁ -C ₁₀ alkane group, C ₁ -C ₁₀ alkoxy group, C ₁ -C ₁₀ alkanoyl group, C ₁ One of ~C ₁₀ ester groups;

2. according to claim 1, is characterized in that, step (1) described phosphine ligand is selected from the one in the following structures:

R ¹ are respectively selected from hydrogen, sulfonic acid group, halogen, nitrile group, C ₁ -C ₁₀ alkane group, C ₁ -C ₁₀ alkoxy group,

Wherein: R ^x are independently selected from hydrogen, sulfonic acid group, halogen, nitrile group, C ₁ -C ₁₀ alkane group, C ₁ -C ₁₀ alkoxy group, C ₁ -C ₁₀ alkanoyl group, C ₁ ~C ₁₀ ester group or C ₁ ~C ₁₀ sulfonate group;

3. according to claim 1, it is characterized in that, described organic solvent is selected from the one in methanol, ethanol, n-propanol, Virahol, ethylene glycol, 1,3-propanediol and glycerol;

4. according to claim 1, it is characterized in that, described molecular sieve is respectively selected from MCM-41, ZSM-5, β-Zeolite, ZSM-35 (100), ZSM-35 (10) and ZSM-23, ZSM -22, ZSM-11, KIT-6, SBA-15, MCM-22, MCM-48, SSZ-13, UIO-66, titanium silicon molecular sieve TS-1, SAPO-34, SAPO-11, silicon oxide nanospheres , mesoporous silica, hierarchical porous silica microspheres, solid silica, carbon molecular sieve, 3A molecular sieve, 4A molecular sieve, 5A molecular sieve, 13X molecular sieve, Y-type molecular sieve, COF organic framework material, S-1 all silicon One or several kinds of molecular sieves;

5. according to claim 1, is characterized in that, reaction temperature is 60～200 ℃;

6. According to claim 1, characterized in that the pressure of H ₂ /CO is 3/3bar˜100/100bar.

Compared with prior art, the present invention has following remarkable effect:

1. The Rh/phosphine ligand complex and molecular sieve co-catalyst provided by the present invention are used for the acetalization reaction of 1-alkene, both of which have high catalytic rate (TON up to 43000) and substrate applicability.

2. The Rh/phosphine ligand complex and the molecular sieve co-catalyst provided by the present invention are used for the acetalization reaction of 1-alkene, and both have high regioselectivity (l/b=30.5-99.8).

Detailed ways

Below in conjunction with embodiment the present invention is described in further detail and completely.

Example 1

The Rh/phosphine ligand complex used in the following examples and the molecular sieve cocatalyst are prepared by the following reaction process:

In the glove box, add phosphine ligand (1.16mg), Rh(acac)(CO) ₂ (0.1mg), molecular sieve (40.0mg), organic alcohol (5.0mL) into the autoclave and stir to obtain Rh/ Phosphine ligand complex and molecular sieve cocatalyst.

Example 2

Acetalization of 1-Pentene (Substrate: Catalyst = 1×10 ⁴ ) and EtOH Catalyzed by Rh/Phosphine Ligand Complex and Molecular Sieve Cocatalyst

In a glove box, BINAPa (1.16 mg), Rh(acac)(CO) ₂ (0.1 mg), ZSM-35(10) (40.0 mg), EtOH (5.0 mL), 1-pentene (0.42 mL) , decane (16 μL) was added into the autoclave and stirred, the mixture was purged three times with H ₂ and then filled with CO (20 bar) and H ₂ (20 bar). Then the autoclave was stirred and reacted in an oil bath at 120° C. for 24 h. After the reaction is completed, wait until it cools down to room temperature, centrifuge and measure the gas phase. The yield was 97%, the l/b ratio was 77.1, and the TON value was 10000.

Example 3

Acetalization of 1-Hexene (Substrate: Catalyst = 1×10 ⁴ ) and EtOH Catalyzed by Rh/Phosphine Ligand Complex and Molecular Sieve Cocatalyst

In a glove box, BINAPa (1.16 mg), Rh(acac)(CO) ₂ (0.1 mg), ZSM-35(10) (40.0 mg), EtOH (5.0 mL), 1-hexene (0.47 mL) , decane (16 μL) was added into the autoclave and stirred, the mixture was purged three times with H ₂ and then filled with CO (20 bar) and H ₂ (20 bar). Then the autoclave was stirred and reacted in an oil bath at 120° C. for 24 h. After the reaction is completed, wait until it cools down to room temperature, centrifuge and measure the gas phase. The yield was 98%, the l/b ratio was 51.2, and the TON value was 9970.

Example 4

Acetalization of 1-heptene (substrate: catalyst = 1×10 ⁴ ) and EtOH catalyzed by Rh/phosphine ligand complex and molecular sieve cocatalyst

In a glove box, BINAPa (1.16 mg), Rh(acac)(CO) ₂ (0.1 mg), ZSM-35(10) (40.0 mg), EtOH (5.0 mL), 1-heptene (0.54 mL) , decane (16 μL) was added into the autoclave and stirred, the mixture was purged three times with H ₂ and then filled with CO (20 bar) and H ₂ (20 bar). Then the autoclave was stirred and reacted in an oil bath at 120° C. for 24 h. After the reaction is completed, wait until it cools down to room temperature, centrifuge and measure the gas phase. The yield was 94%, the l/b ratio was 56.4, and the TON value was 9950.

Example 5

Acetalization of 1-octene (substrate: catalyst = 1×10 ⁴ ) and EtOH catalyzed by Rh/phosphine ligand complex and molecular sieve cocatalyst

In a glove box, BINAPa (1.16 mg), Rh(acac)(CO) ₂ (0.1 mg), ZSM-35(10) (40.0 mg), EtOH (5.0 mL), 1-octene (0.60 mL) , decane (16 μL) was added into the autoclave and stirred, the mixture was purged three times with H ₂ and then filled with CO (20 bar) and H ₂ (20 bar). Then the autoclave was stirred and reacted in an oil bath at 120° C. for 24 h. After the reaction is completed, wait until it cools down to room temperature, centrifuge and measure the gas phase. The yield was 93%, the l/b ratio was 33.1, and the TON value was 9950.

Example 6

Rh/phosphine ligand complex and molecular sieve cocatalyst catalyze the acetalization reaction of 1-nonene (substrate: catalyst = 1×10 ⁴ ) and EtOH

In a glove box, BINAPa (1.16 mg), Rh(acac)(CO) ₂ (0.1 mg), ZSM-35(10) (40.0 mg), EtOH (5.0 mL), 1-nonene (0.66 mL) , decane (16 μL) was added into the autoclave and stirred, the mixture was purged three times with H ₂ and then filled with CO (20 bar) and H ₂ (20 bar). Then the autoclave was stirred and reacted in an oil bath at 120° C. for 24 h. After the reaction is completed, wait until it cools down to room temperature, centrifuge and measure the gas phase. The yield was 92%, the l/b ratio was 33.8, and the TON value was 9780.

Example 7

Acetalization of 1-Decene (Substrate: Catalyst = 1×10 ⁴ ) and EtOH Catalyzed by Rh/Phosphine Ligand Complex and Molecular Sieve Cocatalyst

In a glove box, BINAPa (1.16 mg), Rh(acac)(CO) ₂ (0.1 mg), ZSM-35(10) (40.0 mg), EtOH (5.0 mL), 1-decene (0.66 mL) , decane (16 μL) was added into the autoclave and stirred, the mixture was purged three times with H ₂ and then filled with CO (20 bar) and H ₂ (20 bar). Then the autoclave was stirred and reacted in an oil bath at 120° C. for 24 h. After the reaction is completed, wait until it cools down to room temperature, centrifuge and measure the gas phase. The yield was 84%, the l/b ratio was 30.5, and the TON value was 9930.

Example 8

Acetalization of Cyclohexene (Substrate: Catalyst = 1×10 ⁴ ) and EtOH Catalyzed by Rh/Phosphine Ligand Complex and Molecular Sieve Cocatalyst

In a glove box, BINAPa (1.16 mg), Rh(acac)(CO) ₂ (0.1 mg), ZSM-35(10) (40.0 mg), EtOH (5.0 mL), cyclohexene (0.39 mL), Decane (16 μL) was added to the autoclave and stirred, the mixture was purged three times with H ₂ and then filled with CO (20 bar) and H ₂ (20 bar). Then the autoclave was stirred and reacted in an oil bath at 120° C. for 24 h. After the reaction is completed, wait until it cools down to room temperature, centrifuge and measure the gas phase. The yield was 84%, and the TON value was 9160.

Example 9

Acetalization of 1-Hexene (Substrate: Catalyst = 1×10 ⁴ ) and MeOH Catalyzed by Rh/Phosphine Ligand Complex and Molecular Sieve Cocatalyst

In a glove box, BINAPa (1.16 mg), Rh(acac)(CO) ₂ (0.1 mg), ZSM-35(10) (40.0 mg), MeOH (5.0 mL), 1-hexene (0.47 mL) , decane (16 μL) was added into the autoclave and stirred, the mixture was purged three times with H ₂ and then filled with CO (20 bar) and H ₂ (20 bar). Then the autoclave was stirred and reacted in an oil bath at 120° C. for 24 h. After the reaction is completed, wait until it cools down to room temperature, centrifuge and measure the gas phase. The yield was 98%, the l/b ratio was 75.5, and the TON value was 9790.

Example 10

Rh/phosphine ligand complex and molecular sieve co-catalyst the acetalization reaction of 1-hexene (substrate: catalyst = 1×10 ⁴ ) and ⁿ PrOH

In a glove box, BINAPa (1.16 mg), Rh(acac)(CO) ₂ (0.1 mg), ZSM-35(10) (40.0 mg), ⁿ PrOH (5.0 mL), 1-hexene (0.47 mL ), decane (16 μL) were added into the autoclave and stirred, the mixture was purged three times with H ₂ , and then filled with CO (20 bar) and H ₂ (20 bar). Then the autoclave was stirred and reacted in an oil bath at 120° C. for 24 h. After the reaction is completed, wait until it cools down to room temperature, centrifuge and measure the gas phase. The yield was 93%, the l/b ratio was 99.8, and the TON value was 10000.

Example 11

Acetalization of 1-Hexene (Substrate: Catalyst = 1×10 ⁴ ) and ⁿ BuOH Catalyzed by Rh/Phosphine Ligand Complex and Molecular Sieve Cocatalyst

In a glove box, BINAPa (1.16mg), Rh(acac)(CO) ₂ (0.1mg), ZSM-35(10) (40.0mg), ^nBuOH (5.0mL), 1-hexene (0.47mL ), decane (16 μL) were added into the autoclave and stirred, the mixture was purged three times with H ₂ , and then filled with CO (20 bar) and H ₂ (20 bar). Then the autoclave was stirred and reacted in an oil bath at 120° C. for 24 h. After the reaction is completed, wait until it cools down to room temperature, centrifuge and measure the gas phase. The yield was 91%, the l/b ratio was 77.0, and the TON value was 10000.

Example 12

Acetalization of 1-Hexene (Substrate: Catalyst = 1×10 ⁴ ) and (CH ₂ OH) ₂ Catalyzed by Rh/Phosphine Ligand Complex and Molecular Sieve Cocatalyst

In a glove box, BINAPa (1.16 mg), Rh(acac)(CO) ₂ (0.1 mg), ZSM-35(10) (40.0 mg), (CH ₂ OH) ₂ (5.0 mL), 1-hexane Alkene (0.47 mL), decane (16 μL) were added into the autoclave and stirred, the mixture was purged with H ₂ three times, and then filled with CO (20 bar) and H ₂ (20 bar). Then the autoclave was stirred and reacted in an oil bath at 120° C. for 24 h. After the reaction is completed, wait until it cools down to room temperature, centrifuge and measure the gas phase. The yield was 99%, the l/b ratio was 86.3, and the TON value was 10000.

Example 13

Acetalization of 1-Hexene (Substrate: Catalyst = 5×10 ⁴ ) and MeOH Catalyzed by Rh/Phosphine Ligand Complex and Molecular Sieve Cocatalyst

In a glove box, BINAPa (0.23 mg), Rh(acac)(CO) ₂ (0.02 mg), ZSM-35(10) (40.0 mg), MeOH (5.0 mL), 1-hexene (0.47 mL) , decane (16 μL) was added into the autoclave and stirred, the mixture was purged three times with H ₂ and then filled with CO (20 bar) and H ₂ (20 bar). Then the autoclave was stirred and reacted in an oil bath at 120° C. for 24 h. After the reaction is completed, wait until it cools down to room temperature, centrifuge and measure the gas phase. The yield was 82%, the l/b ratio was 84.6, and the TON value was 43000.

The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art can still understand the foregoing embodiments. Modifications are made to the technical solutions described, or equivalent replacements are made to some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions claimed in the present invention.

Claims (6)

1. a synthetic method of acetal, it is characterized in that described method is: under the effect of Rh/phosphine ligand complex and molecular sieve co-catalyst as shown in general formula 1, alkene I, H ₂ /CO and Organic alcohol heating reaction; After the reaction is complete, centrifuge the molecular sieve, and obtain the acetal II shown in the general formula 1 through vacuum distillation;

R are independently selected from hydrogen, C ₁ -C ₁₀ alkane groups, C ₁ -C ₁₀ alkoxy groups,

wherein R ^x are independently selected from hydrogen, hydroxyl, sulfonic acid group, halogen, nitrile group, C ₁ -C ₁₀ alkane group, C ₁ -C ₁₀ alkoxy group, C ₁ -C ₁₀ alkanoyl group, C ₁ One of ~C ₁₀ ester groups. 2. according to claim 1, is characterized in that, step (1) described phosphine ligand is selected from the one in the following structures:

R ¹ are respectively selected from hydrogen, sulfonic acid group, halogen, nitrile group, C ₁ -C ₁₀ alkane group, C ₁ -C ₁₀ alkoxy group,

Wherein: R ^x are independently selected from hydrogen, sulfonic acid group, halogen, nitrile group, C ₁ -C ₁₀ alkane group, C ₁ -C ₁₀ alkoxy group, C ₁ -C ₁₀ alkanoyl group, C ₁ -C ₁₀ ester group or C ₁ -C ₁₀ sulfonate group. 3. according to claim 1, it is characterized in that, described organic solvent is selected from the one in methanol, ethanol, n-propanol, Virahol, ethylene glycol, 1,3-propanediol and glycerol. 4. according to claim 1, it is characterized in that, described molecular sieve is respectively selected from MCM-41, ZSM-5, β-Zeolite, ZSM-35 (100), ZSM-35 (10) and ZSM-23, ZSM -22, ZSM-11, KIT-6, SBA-15, MCM-22, MCM-48, SSZ-13, UIO-66, titanium silicon molecular sieve TS-1, SAPO-34, SAPO-11, silicon oxide nanospheres , mesoporous silica, hierarchical porous silica microspheres, solid silica, carbon molecular sieve, 3A molecular sieve, 4A molecular sieve, 5A molecular sieve, 13X molecular sieve, Y-type molecular sieve, COF organic framework material, S-1 all silicon One and several kinds of molecular sieves. 5. according to claim 1, is characterized in that, reaction temperature is 60～200 ℃. 6. According to claim 1, characterized in that the pressure of H ₂ /CO is 3/3bar˜100/100bar.