Preparation method of 3-butyl nonanol

Abstract

The invention relates to a preparation method of 3-butyl nonanol, which comprises the following steps: carrying out redox reaction on 2-butyl-1-octanol, NaDCC, a catalyst, a pH (Potential of Hydrogen) regulator and dichloromethane to prepare 2-butyl-1-octanal; the preparation method comprises the following steps: under the condition of protective gas, carrying out Wittig reaction on 2-butyl-1-octanal, PPh3CH3Br and K2CO3, so as to prepare 3-butyl-1-nonene; and carrying out a hydroboration-oxidation reaction on the 3-butyl-1-nonene, BH3. THF, H2O2 and NaOH, so as to prepare the 3-butyl nonanol. The preparation method is simple, convenient and mild in reaction condition.

Description

Technical Field

[0001] The invention belongs to the technical field of chemical synthesis, and particularly relates to a method for preparing 3-butyl nonanol. Background Art

[0002] 3-Butylnonanol is an intermediate material, commonly used in the synthesis of surfactants, antioxidants, textile printing and dyeing auxiliaries, lubricant additives, pesticide emulsifiers, resin modifiers, resins, rubber stabilizers, cationic lipids, etc.

[0003] At present, the preparation methods of 3-butyl nonanol and its structural analogs mainly include the following categories:

[0004] (1) The catalytic hydrogenation method disclosed in GB2451325, US3952068 and US3887624, that is, CO is selectively added to the end of the vinylidene group to generate the corresponding alcohol:

[0005]

[0006] (2) The vinylidene-containing compound disclosed in JP2005298443 and US3952068 is added to polyformaldehyde to generate an enol, and then catalytically hydrogenated and reduced to generate the corresponding alcohol:

[0007]

[0008] (3) CN107935854 discloses the synthesis of the corresponding 2-enoic acid ethyl ester from a ketocarbonyl group and triethyl phosphoacetate, followed by catalytic hydrogenation reduction to generate the corresponding ester, and finally the ester is reduced with sodium borohydride to generate the corresponding alcohol:

[0009]

[0010] (4) CN114728887 and WO2022159472 disclose the reaction of an ester with a Grignard reagent to generate a corresponding ester, which is then reduced under the action of lithium aluminum hydride to generate a corresponding alcohol:

[0011]

[0012] (5) The catalytic hydrogenation method disclosed in US20200399197 and WO2019045810, that is, CO is selectively added to the end of the vinylidene group to generate the corresponding aldehyde, and then the aldehyde is catalytically hydrogenated to generate the corresponding alcohol:

[0013] .

[0015] It can be seen that the current methods for preparing 3-butyl nonanol and its structural analogs are mostly catalytic hydrogenation methods or require the use of relatively dangerous reagents such as lithium aluminum hydride. Among them, the catalytic hydrogenation method requires high temperature and high pressure reaction, and is a three-phase reaction, with high stirring requirements and relatively large operation difficulty; lithium aluminum hydride reacts violently, explosively decomposes when exposed to water, and the experiment is relatively dangerous. Therefore, it is necessary to provide a method for preparing 3-butyl nonanol that is simple to operate and highly safe. Summary of the invention

[0016] The invention provides a method for preparing 3-butyl nonanol with simple operation and mild reaction conditions.

[0017] A method for preparing 3-butyl nonanol comprises the following steps:

[0018] 2-butyl-1-octanol is reacted with NaDCC, a catalyst, a pH regulator and dichloromethane through an oxidation-reduction reaction to prepare 2-butyl-1-octanal, wherein the pH regulator is used to adjust the pH of the reaction system for preparing 2-butyl-1-octanal to 5-8, and the catalyst includes or is NaBr and TEMPO;

[0019] Under protective gas conditions, the 2-butyl-1-octanal is reacted with PPh3CH3Br and K2CO3 via Wittig reaction to prepare 3-butyl-1-nonene; and

[0020] The 3-butyl-1-nonene is reacted with BH3·THF, H2O2 and NaOH through hydroboration-oxidation to prepare 3-butylnonanol.

[0021] In some embodiments, the molar ratio of NaDCC to 2-butyl-1-octanol is (0.5-0.65):1.

[0022] In some embodiments, the reaction temperature of the redox reaction for preparing 2-butyl-1-octanal is -5°C to 5°C.

[0023] In some embodiments, the steps of preparing 2-butyl-1-octanal include:

[0024] Mixing 2-butyl-1-octanol, dichloromethane, the pH adjuster and the catalyst at -5°C to prepare a first mixture; and

[0025] When the temperature of the first mixture is between -5°C and 5°C, an aqueous solution of NaDCC is added to the first mixture to react and prepare 2-butyl-1-octanal.

[0026] In some embodiments, the pH adjuster includes one or both of the following: KHCO 3 and NaHCO 3 .

[0027] In some embodiments, the steps of preparing 3-butyl-1-nonene include:

[0028] Under protective gas conditions, 3-butyl-1-nonene is mixed with PPh3CH3Br, K2CO3 and an organic solvent and subjected to a Wittig reaction to prepare a third mixture containing 3-butyl-1-nonene, wherein the organic solvent used to prepare the third mixture includes or is one or two of the following: tetrahydrofuran and dimethyl sulfoxide; and

[0029] The 3-butyl-1-nonene in the third mixture is purified to obtain purified 3-butyl-1-nonene.

[0030] In some embodiments, the reaction temperature of the Wittig reaction is 75°C to 100°C;

[0031] In some embodiments, the reaction time of the Wittig reaction is 20 h to 30 h.

[0032] In some embodiments, the step of preparing 3-butyl-1-nonanol comprises:

[0033] At -5°C to 5°C, 3-butyl-1-nonene, an organic solvent and BH3·THF are mixed and reacted to prepare a sixth mixture;

[0034] At -5°C to 5°C, after adding NaOH to the sixth mixture for reaction, H2O2 is added to prepare a seventh mixture containing 3-butyl-1-nonanol; and

[0035] The 3-butyl-1-nonanol in the seventh mixture is purified to obtain purified 3-butyl-1-nonanol. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 is the NMR spectrum of 3-butyl-1-nonene;

[0037] Figure 2 This is the NMR spectrum of 3-butylnonanol. DETAILED DESCRIPTION

[0038] For ease of understanding of the present application, the present application will be described more fully below, and the present application can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the present application disclosure more thorough and comprehensive. The terms "first", "second", etc. are only used for descriptive purposes and cannot be interpreted as indicating or implying relative importance. The terms "and / or" or "and / or" refer to any and all combinations including one or more related listed items.

[0039] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0040] An embodiment of the present invention provides a method for preparing 3-butylnonanol, which comprises step S10, step S20 and step S30.

[0041] Step S10: Using 2-butyl-1-octanol (i.e. ) and sodium dichloroisocyanurate (NaDCC), a catalyst, a pH regulator and dichloromethane are subjected to redox reaction to prepare 2-butyl-1-octanal (i.e.

[0042] Commonly used reagents for preparing aldehydes from alcohols include heavy metal reagents (such as pyridinium chlorochromate (PCC), pyridinium dichromate (PDC), Jones reagent, etc.), Dess-Martin periodinane (DMP) and 2-iodobenzoic acid (IBX). In step S10, NaDCC is used as an oxidant to oxidize 2-butyl-1-octanol to 2-butyl-1-octanal. NaDCC as an oxidant for oxidizing 2-butyl-1-octanol to 2-butyl-1-octanal in step S10 has at least the following advantages: (1) Compared with heavy metal reagents, NaDCC is more environmentally friendly. (2) DMP is expensive and the post-scale processing is more troublesome. Compared with DMP, NaDCC is cheaper and the subsequent processing is simpler. (3) Although IBX is moderately priced and has good universal applicability, it is easy to over-oxidize and produce impurity acids. If the amount of IBX is reduced, the alcohol cannot be completely oxidized to aldehyde. In addition, the post-processing process of the reaction with IBX is relatively complicated, and the impurity acids produced by the reaction need to be filtered out, and the product needs to be extracted and recovered from the impurity acids by beating with solvents. Although NaDCC will also produce impurity acids due to over-oxidation, by controlling the amount of NaDCC, the amount of impurity acids produced can be controlled to less than 0.5%. Therefore, NaDCC reacts cleanly as an oxidant, and the target aldehyde can be obtained by simply filtering and separating the liquid to remove the organic solvent after the reaction. (4) The reaction conditions of NaDCC as an oxidant are mild, and no high temperature or pressure is required, and no dangerous reagents are required to participate in the reaction.

[0043] In some embodiments, the molar ratio of NaDCC to 2-butyl-1-octanol is (0.5-0.65):1. When the molar ratio of NaDCC to 2-butyl-1-octanol is (0.5-0.65):1, less impurity acid is produced, and the target aldehyde can be obtained by simple filtration and evaporation after the reaction. Even at a certain ratio, the product can be directly subjected to the next reaction without further purification. In some optional specific examples, the molar ratio of NaDCC to 2-butyl-1-octanol is 0.55:1, 0.6:1, 0.63:1 or 0.65:1. In some embodiments, the molar ratio of NaDCC to 2-butyl-1-octanol is (0.6-0.63):1.

[0044] The catalyst in step S10 includes or is one or two of the following: NaBr and 2,2,6,6-tetramethylpiperidine-1-oxide (TEMPO).

[0045] The pH adjuster in step S10 is used to adjust the pH of the reaction system for preparing 2-butyl-1-octanal to 5-8.

[0046] In some embodiments, the pH adjuster in step S10 includes one or two of the following: KHCO3 and NaHCO3. It is understood that in other embodiments, the pH adjuster in step S10 is not limited to the above, and can also be other substances.

[0047] In some embodiments, the reaction temperature of the redox reaction for preparing 2-butyl-1-octanal in step S10 is -5°C to 5°C.

[0048] In some embodiments, step S10 includes step S11 and step S12.

[0049] Step S11 includes: mixing 2-butyl-1-octanol, dichloromethane, a pH regulator and a catalyst at -5°C to 5°C to prepare a first mixture.

[0050] In some embodiments, the organic solvent and catalyst herein are as described above.

[0051] In an alternative specific example, the pH adjuster is KHCO3, and the catalyst is NaBr and TEMPO.

[0052] In an optional specific example, the temperature for preparing the first mixture is -3°C, -1°C, 0°C, 1°C, 3°C or 5°C. In some embodiments, the temperature for preparing the first mixture is 0°C to 5°C.

[0053] Step S12 includes: when the temperature of the first mixture is between -5°C and 5°C, adding an aqueous solution of NaDCC to the first mixture for reaction to prepare a second mixture containing 2-butyl-1-octanal.

[0054] In some embodiments, the reaction time of the first mixture and the aqueous solution of NaDCC is 2h to 4h. In an optional specific example, the reaction time of the first mixture and the aqueous solution of NaDCC is 2h, 2.5h, 3h, 3.5h or 4h. In this article, the reaction time of the first mixture and the aqueous solution of NaDCC is counted from the time when the aqueous solution of NaDCC is added, and the reaction time of other reactions is the same, all of which are counted after the addition of the materials is completed.

[0055] In an optional specific example, the aqueous solution of NaDCC is added to the first mixture when the temperature of the first mixture is -3°C, -1°C, 0°C, 1°C, 3°C or 5°C. In some embodiments, the aqueous solution of NaDCC is added to the first mixture when the temperature of the first mixture is 0°C to 5°C.

[0056] In some embodiments, the aqueous solution of NaDCC is added to the first mixture dropwise.

[0057] In some embodiments, after the reaction of the first mixture with the aqueous solution of NaDCC is completed, the reaction product is filtered, the organic phase is collected and the organic solvent in the organic phase is removed. In an optional specific example, the method for removing the organic solvent in the organic phase is vacuum distillation. It is understood that the method for removing the organic solvent in the organic phase is not limited to vacuum distillation, and can also be other methods.

[0058] In some embodiments, step S10 further includes step S13, which includes: purifying the second mixture containing 2-butyl-1-octanal to prepare purified 2-butyl-1-octanal. It is understood that the purification method in step S13 is not particularly limited, for example, column chromatography purification can be used. In other embodiments, step S10 does not include step S13.

[0059] Step S20: Under protective gas conditions, 2-butyl-1-octanal is reacted with PPh3CH3Br and K2CO3 to produce 3-butyl-1-nonene (i.e. ).

[0060] Compared with n-BuLi and t-BuOK, the use of K2CO3 to provide an alkaline environment for the Wittig reaction can make the reaction of 2-butyl-1-octanal more complete.

[0061] In some embodiments, the Wittig reaction is carried out in an organic solvent. In an alternative specific example, the organic solvent of the Wittig reaction includes or is one or two of the following: tetrahydrofuran (THF) and dimethyl sulfoxide (DMSO).

[0062] In some embodiments, the reaction time of the Wittig reaction is 20 h to 30 h. In an optional specific example, the reaction time of the Wittig reaction is 22 h, 24 h, 26 h, 27 h or 29 h.

[0063] In some embodiments, the temperature of the Wittig reaction is 75° C. to 100° C. In an alternative specific example, the temperature of the Wittig reaction is 75° C., 80° C., 85° C., 90° C., 95° C., or 100° C. In some embodiments, the temperature of the Wittig reaction is 75° C. to 85° C. or 85° C. to 100° C.

[0064] In some embodiments, the shielding gas is nitrogen or argon.

[0065] In some embodiments, step S20 includes step S21 and step S22.

[0066] Step S21: Under protective gas conditions, 2-butyl-1-octanal is mixed with PPh3CH3Br, K2CO3 and an organic solvent and subjected to a Wittig reaction to prepare a third mixture containing 3-butyl-1-nonene.

[0067] In some embodiments, the organic solvent, reaction temperature and reaction time in the Wittig reaction are as described above.

[0068] In some embodiments, 2-butyl-1-octanal, PPh3CH3Br, K2CO3 and DMSO are mixed under a nitrogen atmosphere at a temperature of 75°C to 100°C to perform a Wittig reaction to prepare a third mixture containing 3-butyl-1-nonene.

[0069] Step S22: purifying the 3-butyl-1-nonene in the third mixture to obtain purified 3-butyl-1-nonene.

[0070] In some embodiments, the step of purifying 3-butyl-1-nonene in the third mixture includes: mixing the reaction product of the Wittig reaction with water, extracting with ethyl acetate (EA), collecting the organic phase, and then washing the organic phase with saturated brine and removing the organic solvent in the organic phase to obtain a fourth mixture; mixing the fourth mixture with a mixture of EA and n-heptane, filtering and removing the organic solvent in the filtrate to obtain a fifth mixture; and performing column chromatography on the fifth mixture to prepare purified 3-butyl-1-nonene.

[0071] In some embodiments, the volume ratio of EA to n-heptane in the step of mixing the fourth mixture with the mixed solution of EA and n-heptane for slurrying is 1:(8-12). In an optional specific example, the volume ratio of EA to n-heptane in the step of mixing the fourth mixture with the mixed solution of EA and n-heptane for slurrying is 1:8, 1:9, 1:10 or 1:11.

[0072] In some embodiments, the method of removing the organic solvent in the organic phase in the step of purifying the 3-butyl-1-nonene in the third mixture includes or is rotary evaporation (rotary evaporation), such as reduced pressure rotary evaporation. It is understood that the method of removing the organic solvent in the organic phase in the step of purifying the 3-butyl-1-nonene in the third mixture is not limited to rotary evaporation, but can also be other methods.

[0073] It can be understood that, in other embodiments, the method for purifying 3-butyl-1-nonene in the third mixture is not limited to the above method, and other methods may be used.

[0074] Step S30: 3-butyl-1-nonene is reacted with BH3·THF, H2O2 and NaOH through a hydroboration-oxidation reaction to prepare 3-butyl nonanol (i.e. ).

[0075] The yield of the conventional method of preparing alcohol from olefin using 9-boranebicyclo[3.3.1]nonane is 71% (WO2011094225A1), the yield of the method of preparing alcohol from olefin using dicyclohexylborane and sodium perborate is 76% (Kabalka GW, Yu S, Li N S. Selective hydroboration of alkenes and alkynes in the presence of aldehydes and ketones [J]. Canadian journal of chemistry, 1998, 76 (6): 800-805), and the yield of the method of preparing alcohol from olefin using boron trifluoride etherate is 59% to 79% (Fujita T, Watanabe S, Suga K, et al. Synthesis of 2-alkyl-3-methyl-2-cyclopentenones from carboxylic acids or methylketones [J]. Journal of Chemical Technology and Biotechnology, 1979, 29(2): 100-106), while the method of preparing alcohol (3-butyl nonanol) from olefin (3-butyl-1-nonene) using BH3·THF, H2O2 and NaOH adopted in the present invention has a better yield, which can reach 91.35%.

[0076] In some embodiments, the reaction temperature of the hydroboration-oxidation reaction is -5°C to 5°C. In an alternative specific example, the reaction temperature of the hydroboration-oxidation reaction is -4°C, -2°C, 0°C, 2°C, 4°C or 5°C. In some embodiments, the reaction temperature of the hydroboration-oxidation reaction is 0°C to 5°C.

[0077] In some embodiments, step S30 includes: a step of purifying the product of the hydroboration-oxidation reaction.

[0078] In some embodiments, step S30 includes step S31, step S32, and step S33.

[0079] Step S31: Mix 3-butyl-1-nonene, an organic solvent and BH3·THF for reaction at -5°C to 5°C to prepare a sixth mixture.

[0080] In some embodiments, the organic solvent in step S31 includes or is one or both of the following: THF and cyclopentyl methyl ether.

[0081] In some embodiments, the reaction time in step S31 is 2 hours to 4 hours. In an optional specific example, the reaction time in step S31 is 2 hours, 2.5 hours, 3 hours, 3.5 hours or 4 hours. In some embodiments, the reaction time in step S31 is 2.5 hours to 4 hours.

[0082] In an optional specific example, the reaction temperature in step S31 is -4°C, -2°C, 0°C, 2°C, 4°C or 5°C. In some embodiments, the reaction temperature in step S31 is 0°C to 5°C.

[0083] In some embodiments, BH3·THF is mixed with 3-butyl-1-nonene and an organic solvent by dropping BH3·THF into a mixture of 3-butyl-1-nonene and an organic solvent.

[0084] Step S32: adding NaOH to the sixth mixture at -5°C to 5°C for reaction, and then adding H2O2 to prepare a seventh mixture containing 3-butylnonanol.

[0085] In some embodiments, the reaction time of the sixth mixture and NaOH is 5 min to 15 min. In an optional specific example, the reaction time of the sixth mixture and NaOH is 5 min, 8 min, 10 min, 12 min or 15 min.

[0086] In some embodiments, the reaction time after adding H2O2 is 1.5 h to 3 h. In an optional specific example, the reaction time after adding H2O2 is 1.5 h, 2 h, 2.5 h or 3 h.

[0087] In an optional specific example, the temperature in step S32 is -4°C, -2°C, 0°C, 2°C, 4°C or 5°C. In some embodiments, the temperature in step S32 is 0°C to 5°C.

[0088] Step S33: purifying the 3-butyl nonanol in the seventh mixture to prepare purified 3-butyl nonanol.

[0089] In some embodiments, the step of purifying 3-butylnonanol in the seventh mixture includes: mixing with water after removing the organic solvent in the seventh mixture, extracting with EA, collecting the organic phase, and then removing the organic solvent in the organic phase to obtain an eighth mixture; and subjecting the eighth mixture to column chromatography to prepare purified 3-butylnonanol.

[0090] In some embodiments, the filler used for column chromatography in step S32 is silica gel of 100-400 mesh. In some embodiments, the filler used for column chromatography in step S32 is silica gel of 100-200 mesh, 200-300 mesh or 300-400 mesh. In some embodiments, the filler used for column chromatography in step S32 is silica gel of 300-400 mesh. When the filler used for column chromatography is silica gel of 300-400 mesh, the purification effect can be better, the purity of the purified product is higher, and the maximum unknown single impurity (single impurity) content does not exceed 0.2%.

[0091] In some embodiments, the eluent used for column chromatography in step S32 is a mixture of EA and n-heptane. In some embodiments, the eluent used for column chromatography in step S32 is a mixture of EA and n-heptane, wherein the volume ratio of EA to n-heptane is: (2-10): 100. In an optional specific example, the eluent used for column chromatography in step S32 is a mixture of EA and n-heptane, wherein the volume ratio of EA to n-heptane is: 1:10, 9:100, 2:25, 7:100, 3:50 or 1:20.

[0092] In some embodiments, the method for removing the organic solvent in the organic phase in the step of purifying the 3-butyl nonanol in the seventh mixture is rotary evaporation (rotary evaporation), such as reduced pressure rotary evaporation. It is understood that the method for removing the organic solvent in the organic phase in the step of purifying the 3-butyl nonanol in the seventh mixture is not limited to rotary evaporation, but can also be other methods. In addition, it is understood that in other embodiments, the method for purifying the 3-butyl nonanol in the seventh mixture is not limited to the above, but can also be other methods.

[0093] The preparation method of 3-butyl nonanol has at least the following advantages: compared with the conventional method of preparing 3-butyl nonanol by a catalytic hydrogenation method with relatively high operation difficulty or a lithium aluminum hydride method with high risk factor, the preparation method of 3-butyl nonanol adopts 2-butyl-1-octanol which is easily available on the market as a synthesis starting material, oxidizes 2-butyl-1-octanol to aldehyde, and then obtains a terminal olefin with one more carbon by a phosphorus ylide methyl reagent, and then obtains 3-butyl nonanol by a hydroboration-oxidation reaction of the terminal olefin. The synthesis route is short, the operation is simple, the reaction conditions are mild, the reaction substrate is easily available, and the cost is low.

[0094] Example

[0095] The following is a detailed description in conjunction with specific examples. The following examples do not include other components except for inevitable impurities unless otherwise specified. The reagents and instruments used in the examples are conventionally selected in the art unless otherwise specified. The experimental methods for which specific conditions are not specified in the examples are implemented according to conventional conditions, such as the conditions described in the literature, books, or methods recommended by the manufacturer.

[0096] Example 1

[0097] 1. Synthesis of 3-butyl-1-nonene (8-A2)

[0098]

[0099] Experimental process:

[0100] Add 2-butyl-1-octanol (8-A0, 15.0 g, 80.50 mmol), DCM (90 mL), NaBr (0.82 g), TEMPO (0.61 g), KHCO3 (6.37 g) to a 500 mL single-mouth bottle, place it in a 0°C low-temperature tank, and when the internal temperature drops to about 5°C, dissolve NaDCC (10.62 g, 48.30 mmol) in 90 mL of water and drip it into the reaction. After the dripping, keep the temperature for 3 hours. Filter to remove the filter cake, separate the filtrate, collect the organic phase, and remove DCM by vacuum distillation at 35°C to obtain 15 g of crude 2-butyl-1-octanal (8-A1). After thin layer chromatography (TLC) detection, the content of impurity acid is less than 0.5%, and the content of 8-A1 is greater than 95%. It is directly used for the next step without purification.

[0101] 8-A1 (15.0 g), DMSO (150 mL), methyltriphenylphosphonium bromide (57.51 g, 161 mmol), potassium carbonate powder (20.2 g) were added to a 250 mL single-mouth bottle, and the mixture was reacted at 100 ° C for 24 h under the protection of a nitrogen balloon. According to thin layer chromatography (TLC), the content of 2-butyl-1-octanal in the Wittig reaction product was less than 2%, and the content of 3-butyl-1-nonene was greater than 95%. The reaction solution was poured into 300 mL of water, and ethyl acetate (200 mL) was added for extraction. The organic phases were combined and washed once with 300 mL of saturated brine. The organic phases were collected and dried to obtain a light yellow solid. The solid was slurried with a mixed solution of ethyl acetate (20 mL) and n-heptane (200 mL), filtered, and the filtrate was dried under reduced pressure at 40° C. to obtain 20.0 g of an orange-yellow liquid, which was purified by column purification (eluted with n-heptane) to obtain 12.35 g of a colorless liquid 3-butyl-1-nonene (8-A2, NMR spectrum see Figure 1 ), purity 98.78%, two-step yield 84.13%.

[0102] 1H NMR (600MHz, CDCl3) δ5.56 (ddd, J=17.0, 10.3, 8.8Hz, 1H), 5.00-4.91 (m, 2H), 1.95 (m, 1H), 1.41-1.21 (m, 16H), 0.93-0.91 (m, 6H).

[0103] GC-MS(EI):(M+H)183.3.

[0104] 2. Synthesis of 8-A3

[0105]

[0106] Experimental process:

[0107] Add 3-butyl-1-nonene (8-A2, 8.0 g, 43.87 mmol) and THF (160 mL) to a 500 mL single-mouth bottle, place in a 0°C low-temperature tank, and slowly drop 1M BH3·THF (102 mL) into the reaction system when the internal temperature drops below 5°C. After the drop is complete, keep the temperature for 3 hours. Slowly drop 3M NaOH aqueous solution (41 mL) into the reaction system, react for 10 minutes, then add 30% H2O2 (24 mL) into the reaction system and react for 2 hours. The solvent was dried under reduced pressure at 40°C, 100 mL of water was added, and the mixture was extracted with EA (100 mL). The organic phase was dried under reduced pressure at 40°C to obtain a colorless liquid, which was purified by column chromatography (filler: 300-400 mesh silica gel, EA: n-heptane = 1:10 (v:v) elution) to obtain 8.03 g of colorless liquid 3-butyl nonanol (8-A3, NMR spectrum see Figure 2 ), purity 98.5%, yield 91.35%, single impurity content is 0.19%.

[0108] 1 H NMR (600MHz, CDCl3) δ3.69 (t, J = 7.1Hz, 2H), 1.60-1.50 (m, 2H), 1.48-1.39 (m, 2H), 1.38-1.22 (m, 16H), 0.92 (m, 6H).

[0109] GC-MS(EI):(M+H)201.4.

[0110] Example 2

[0111] The preparation method of 3-butyl-1-nonene from 2-butyl-1-octanal in this embodiment is substantially the same as that in Example 1, except that the reagents and steps used to prepare 3-butyl-1-nonene from 2-butyl-1-octanal are different. In this embodiment, n-BuLi is used to provide an alkaline environment for the Wittig reaction, the organic solvent is THF, and the reaction temperature is 25°C. The steps of preparing 3-butyl-1-nonene from 2-butyl-1-octanal in this embodiment include:

[0112]

[0113] Add methyl triphenylphosphonium bromide (19.38 g, 54.25 mmol) and 25 mL of anhydrous THF to a 250 mL single-mouth bottle, place it in a 0°C low-temperature tank under nitrogen protection, slowly drop 20 mL of 2.5 M n-butyl lithium n-hexane solution, keep warm and stir for 30 minutes after the drop, finally add 8-A1 (5.0 g, 27.13 mmol), transfer to 25°C and react for 24 hours. According to thin layer chromatography (TLC) detection, the content of 2-butyl-1-octanal in the Wittig reaction product is 90% to 95%, and the content of 3-butyl-1-nonene is 5% to 10%. The Wittig reaction product was poured into 100 mL of water, and ethyl acetate (100 mL) was added for extraction. The organic phases were combined and washed once with 100 mL of saturated brine. The organic phases were collected and dried to obtain a light yellow solid. The solid was slurried with a mixed solution of ethyl acetate (10 mL) and n-heptane (100 mL), filtered, and the filtrate was dried under reduced pressure at 40° C. to obtain 6.5 g of a light yellow liquid, which was purified by column (eluted with n-heptane) to obtain 425 mg of a colorless liquid 3-butyl-1-nonene 8-A2, with a two-step yield of 8.6%.

[0114] 1 H NMR (600MHz, CDCl3) δ5.54 (ddd, J=17.0, 10.3, 8.8Hz, 1H), 4.98-4.90 (m, 2H), 1.94 (m, 1H), 1.40-1.21 (m, 16H), 0.92-0.90 (m, 6H).

[0115] GC-MS(EI):(M+H)183.3.

[0116] Example 3

[0117] The preparation method of 3-butyl-1-nonene from 2-butyl-1-octanal in this embodiment is substantially the same as that in Example 1, except that the reagents and steps used to prepare 3-butyl-1-nonene from 2-butyl-1-octanal are different. In this embodiment, t-BuOK is used to provide an alkaline environment for the Wittig reaction, THF is used as the organic solvent, and the reaction temperature is 25° C. The steps of preparing 3-butyl-1-nonene from 2-butyl-1-octanal in this embodiment include:

[0118]

[0119] Add methyl triphenylphosphonium bromide (19.38 g, 54.25 mmol) and 25 mL of anhydrous THF to a 250 mL single-mouth bottle, place it in a 0°C low-temperature tank under nitrogen protection, slowly add t-BuOK (5.48 g, 48.83 mmol), keep warm and stir for 30 minutes after the addition, finally add 8-A1 (5.0 g, 27.13 mmol), and react at 25°C for 24 hours. According to thin layer chromatography (TLC) detection, the content of 2-butyl-1-octanal in the Wittig reaction product is 90% to 95%, and the content of 3-butyl-1-nonene is 5% to 10%. The Wittig reaction product was poured into 100 mL of water, and ethyl acetate (100 mL) was added for extraction. The organic phases were combined and washed once with 100 mL of saturated brine. The organic phases were collected and dried to obtain a light yellow solid. The solid was slurried with a mixed solution of ethyl acetate (10 mL) and n-heptane (100 mL), filtered, and the filtrate was dried under reduced pressure at 40° C. to obtain 6.7 g of a light yellow liquid, which was purified by column (eluted with n-heptane) to obtain 350 mg of a colorless liquid 3-butyl-1-nonene 8-A2, with a two-step yield of 7.1%.

[0120] Example 4

[0121] The preparation method of 3-butyl-1-nonene from 2-butyl-1-octanal in this embodiment is substantially the same as that in Example 3, except that the reaction temperature in the step of preparing 3-butyl-1-nonene from 2-butyl-1-octanal is different. The reaction temperature in the step of preparing 3-butyl-1-nonene from 2-butyl-1-octanal in this embodiment is 66° C. The step of preparing 3-butyl-1-nonene from 2-butyl-1-octanal in this embodiment includes:

[0122]

[0123] Add methyl triphenylphosphonium bromide (19.38 g, 54.25 mmol) and 25 mL of anhydrous THF to a 250 mL single-mouth bottle, place it in a 0 ° C low temperature tank under nitrogen protection, slowly add t-BuOK (5.48 g, 48.83 mmol), keep warm and stir for 30 minutes after the addition, finally add 8-A1 (5.0 g, 27.13 mmol), turn to 66 ° C and react for 24 hours. According to thin layer chromatography (TLC) detection, the content of 2-butyl-1-octanal in the Wittig reaction product is 90% to 95%, and the content of 3-butyl-1-nonene is 5% to 10%. The Wittig reaction product was poured into 100 mL of water, and ethyl acetate (100 mL) was added for extraction. The organic phases were combined and washed once with 100 mL of saturated brine. The organic phases were collected and dried to obtain a light yellow solid. The solid was slurried with a mixed solution of ethyl acetate (10 mL) and n-heptane (100 mL), filtered, and the filtrate was dried under reduced pressure at 40° C. to obtain 6.7 g of a light yellow liquid, which was purified by column (eluted with n-heptane) to obtain 474 mg of a colorless liquid 3-butyl-1-nonene 8-A2, with a two-step yield of 9.6%.

[0124] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0125] The above-described embodiments only express several implementation methods of the present application, which is convenient for understanding the technical solutions of the present application in detail, but cannot be understood as limiting the scope of protection of the patent application. It should be pointed out that, for those of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the scope of protection of the present application. It should be understood that, on the basis of the technical solutions provided by those skilled in the art in the present application, the technical solutions obtained through logical analysis, reasoning or limited experiments are all within the scope of protection of the claims attached to the present application. Therefore, the scope of protection of the patent of the present application shall be based on the contents of the attached claims, and the specification can be used to interpret the contents of the claims.

Claims

1. A method for preparing 3-butyl nonanol, comprising the following steps: 2-butyl-1-octanol is reacted with NaDCC, a catalyst, a pH regulator and dichloromethane through an oxidation-reduction reaction to prepare 2-butyl-1-octanal, wherein the pH regulator is used to adjust the pH of the reaction system for preparing 2-butyl-1-octanal to 5-8, and the catalyst includes or is NaBr and TEMPO; Under protective gas conditions, the 2-butyl-1-octanal is reacted with PPh3CH3Br and K2CO3 via Wittig reaction to prepare 3-butyl-1-nonene; and The 3-butyl-1-nonene is reacted with BH3·THF, H2O2 and NaOH through hydroboration-oxidation to prepare 3-butylnonanol.

2. The preparation method according to claim 1, wherein the molar ratio of NaDCC to 2-butyl-1-octanol is (0.5-0.65):1; And / or, the reaction temperature of the redox reaction for preparing 2-butyl-1-octanal is -5°C to 5°C.

3. The preparation method according to claim 1 or 2, wherein the step of preparing 2-butyl-1-octanal comprises: Mixing 2-butyl-1-octanol, dichloromethane, the pH adjuster and the catalyst at -5°C to prepare a first mixture; and When the temperature of the first mixture is between -5°C and 5°C, an aqueous solution of NaDCC is added to the first mixture to react and prepare 2-butyl-1-octanal.

4. The preparation method according to claim 3, wherein the pH regulator comprises one or two of the following: KHCO3 and NaHCO3.

5. According to the preparation method of claim 1, 2 or 4, the step of preparing 3-butyl-1-nonene comprises: Under protective gas conditions, 3-butyl-1-nonene is mixed with PPh3CH3Br, K2CO3 and an organic solvent and subjected to a Wittig reaction to prepare a third mixture containing 3-butyl-1-nonene, wherein the organic solvent used to prepare the third mixture includes or is one or two of the following: tetrahydrofuran and dimethyl sulfoxide; and The 3-butyl-1-nonene in the third mixture is purified to obtain purified 3-butyl-1-nonene.

6. The preparation method according to claim 5, wherein the reaction temperature of the Wittig reaction is 75°C to 100°C; And / or, the reaction time of the Wittig reaction is 20 h to 30 h.

7. According to the preparation method of claim 1, 2, 4 or 6, the step of preparing 3-butyl-1-nonanol comprises: At -5°C to 5°C, 3-butyl-1-nonene, an organic solvent and BH3·THF are mixed and reacted to prepare a sixth mixture; At -5°C to 5°C, after adding NaOH to the sixth mixture for reaction, H2O2 is added to prepare a seventh mixture containing 3-butyl-1-nonanol; and The 3-butyl-1-nonanol in the seventh mixture is purified to obtain purified 3-butyl-1-nonanol.

Images