羧酸和乙醇反应碳酸二乙酯的作用

发布网友 发布时间：2023-05-18 12:53

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热心网友 时间：2023-10-02 09:51

您好，羧酸和乙醇反应碳酸二乙酯的作用是将羧酸和乙醇反应生成碳酸二乙酯，这是一种常见的有机化学反应。碳酸二乙酯可以用作溶剂、润滑剂、抗菌剂和抗氧化剂，广泛应用于医药、食品、纺织、油漆等行业。此外，碳酸二乙酯还可以用作添加剂，用于改善涂料的抗腐蚀性能，改善涂料的抗氧化性能，增加涂料的耐磨性，改善涂料的抗紫外线性能，以及改善涂料的抗污染性能。

热心网友 时间：2023-10-02 09:52

羧酸和醇的酯化反应实例

1、硫酸作催化剂的酯化反应示例：

4-Amino-3-nitrobenzoic acid (200.0 g) was suspended in ethanol (1030 g).Conc. sulfuric acid (120.0 g) was added dropwise to the mixture over 0.5 h.After the dropwise addition, the mixture was refluxed under heating for 15 h. Apart (422 mL) of ethanol was distilled away at atmospheric pressure, and water(660 mL) was added dropwise to allow precipitation of crystals. To this suspension were added 25% aqueoussodium hydroxide solution (50 mL) and then 2.5% aqueous sodium hydroxidesolution (262 mL), and pH was adjusted to 6.5. The precipitated crystals werecollected by filtration, washed successively with ethanol (531 mL) and water(1069 mL), and dried under reced pressure to give ethyl4-amino-3-nitrobenzoate (200.6 g)。

2 、盐酸（氯化氢）作催化剂的酯化反应示例：



3,4-Diaminobenzoic acid (152 g, 1.0 mol) was stirred with ethanol (2000mL) in a Morton flask. Hydrogen chloride gas was passed through the stirredsuspension for about 2 h. As the gas was absorbed, the slurry became gel-likein character. Ethanol (500 ml.) was added to the reaction mixture to dispersethe gel. The reaction mixture was refluxed 24 h. The mixture was filtered andthe filtrate was evaporated to dryness in vacuo. The filter cake and thefiltrate resie were dissolved in water (9 L). Theaqueous solution was made basic by the addition of solid sodium carbonate. Theproct precipitated from the basic solution. The material was filtered anddried to yield ethyl 3,4-diaminobenzoate (130 g, 72.14%)。

3 、氯化亚砜作催化剂的酯化反应示例：



To a suspension of 6-chloropyridine-2-carboxylic acid (8.3 g, 0.0525mol) in dioxane (25 mL), thionyl chloride (9.4 mL, 0.13 mol) was added and theresulting mixture was stirred at 70℃ for 4 h. The reaction mixture was concentrated invacuo and a mixture of dioxane (8.3 mL) and ethanol (16.6 mL) was added. Thereaction mixture was heated to 70℃ for 2 h, triethylamine (8.3 mL), ethanol (4.1 mL) andwater (8.3 mL) were added and the reaction mixture was again concentrated. Theresie was distributed between diethyl ether (28 mL) and water (18 mL) and thephases were separated. The aqueous layer was extracted with diethyl ether (30mL) and the combined organic layers were dried over MgSO4, filteredand evaporated in vacuo to afford 6-chloropyridine-2-carboxylic acid ethylester (8.82 g, 91%) as oil。

方法二：直接将底物溶液醇中，冷却至0℃，加入少量的氯化亚砜，然后加热回流即可得到酯化产物，起催化作用的还是HCl（SOCl2和醇会迅速反应生成HCl）。

4 、乙酰氯作催化剂的酯化反应示例：



Acetyl chloride (15.3 mmol) was added dropwise to ethanol (50 mL) at 0℃. After 30 min, the acid (7.69 mmol) was added and thereaction mixture was heated at reflux for 15 h. The reaction mixture wasconcentrated and the resie was partitioned between dichloromethane (20 mL)and saturated sodium bicarbonate (10 mL). The aqueous layer was furtherextracted with dichloromethane (20 mL × 2) and the combined organic layers were dried(magnesium sulfate) and concentrated to provide the ester in 94% yield as brown oil。

主要起作用的应该是乙酰氯和乙醇反应生成的HCl。

5、 对甲苯磺酸作催化剂的酯化反应示例：

对甲苯磺酸作酯化催化剂只比硫酸稍弱，仍是一个强酸，其用量与使用硫酸相等分子，其作用相等或相近，使用对甲苯磺酸作为酯化催化剂主要是为了避免硫酸带来的焦化和其他副反应。



A 300-mL, one-necked,round-bottomed flask was equipped with a magnetic stirrer, Dean-Stark trap, and a reflux condenser. The flask was charged with 3.0 g (20 mmol) of L-(+)-tartaric acid, 6.5 g (60 mmol) of benzyl alcohol, 47.5 mg (0.25 mmol) of p-toluenesulfonic acid monohydrateand 40 mL of toluene. The mixture washeated under reflux in an oilbath (about 130℃) for 13 hr.During this period the theoretical amount of water (0.62 mL) was collected. Themixture was allowed to cool to ambient temperature, diluted with ether, and poured into 50 mL of aqueous, saturated sodium bicarbonate. Theorganic phase was separated and the aqueous phase was extracted twice with 20 mL of ether. The combinedorganic phases were dried over sodiumsulfate. The solvent was removed with a rotary evaporator, and the resulting crudeproct was triturated with hexane-ether (20:1, 210 mL) to give white crystals of (−)-dibenzyl tartrate.The precipitate was collected by filtration and washed with hexane-ether (20:1). Thefiltrate was further concentrated to give a second crop. The total yield was 6.2 g (94%), mp 49–50℃

6 、吡啶衍生物作除水剂的酯化反应示例：



A. Ricinelaidicacid S-(2-pyridyl)carbothioate

In a dry,stoppered, 10-mL flask containing a magnetic stirring bar were placed 360 mg (1.2 mmol) of ricinelaidic acid, 2,2'-dipyridyl disulfide (308 mg, 1.4 mmol), benzene (1 mL), and 367mg (1.4 mmol) of triphenylphosphine. The mixture was stirredfor 30 min. The resulting slurry was then dissolved in dry acetonitrile (55mL).

B. Ricinelaidicacid lactone

Dry acetonitrile (100 mL), 3.5 mL of 1 M silver perchlorate in toluene and a magnetic stirring bar were placed in a 500-mL flask equipped with a reflux condenser thatcarries a Hershberg dropping funnel. The solution was heated in an oil bath so that the boiling acetonitrile returns from the condenser at the rate of 5–10 dropsper second. Then the acetonitrile solution of the ricinelaidic acid S-(2-pyridyl)carbothioate was added dropwise ring 1 h through the condenserto the magnetically stirred refluxing silver perchlorate solution. The slightly turbid mixture was boiled foran additional 15 min and the solvent was removed under reced pressure in a rotary evaporator. The resie was diluted with 30 mL of 0.5 M potassium cyanide solution and the mixture containing suspended solidswas extracted with three 50-mL portions of benzene. The benzene extracts were washed with 30 mL of water, dried withanhydrous magnesium sulfate, and filtered, and the solvent was removed underreced pressure. Crude proct was obtained as an oil (710 mg). It can be purified by chromatography on 40 g of silica gel with benzene as eluant. Fractions of 10 mL were collected at 30min intervals. Fractions 7–19 contain 283–296 mg (84–88%) of ricinelaidic acidlactone 。

6 、苯并*衍生物作除水剂的酯化反应示例：



Triethylamine (305ul, 2.2 mmol) was added at roomtemperature to a stirred solution of 1-phenyl-1, 2-ethanediol (280 mg, 2.0mmol) and 1-(benzolyoxy)benzotriazole (503 mg, 2.1 mmol) in CH2Cl2(8 mL). The reaction mixture was stirred at room temperature for 24 h, dilutedwith CH2Cl2 (30 mL), washed with saturated NaHCO3 solution(20 mL), dried over MgSO4, and evaporated to dryness. The crudeproct was subjected to silica gel column chromatography with hexane/ EtOAc(6:1) mixture as an eluent o afford the dibenzoate (34 mg, 5%), the primarymonobenzoate (390 mg, 83%), and the secondary nonobenzoate (42 mg, 9%)

热心网友 时间：2023-10-02 09:52

最佳答案: 羧酸和乙醇反应可以生成碳酸二乙酯(ethylene glycol)。该化合物是一种重要的有机溶剂,广泛用于制造汽车冷却剂、食品加工中的冷凝剂、抗冻剂、血浆保存液以及其它多种用途。

热心网友 时间：2023-10-02 09:53

羧酸和乙醇反应可以生成碳酸二乙酯（ethylene glycol）。该化合物是一种重要的有机溶剂，广泛用于制造汽车冷却剂、食品加工中的冷凝剂、抗冻剂、血浆保存液以及其它多种用途。

热心网友 时间：2023-10-02 09:53

乙醇和羧酸可以反应生成碳酸二乙酯，此反应是一种常见的酯化反应，它能够用来缩合羧酸和醇类物质，从而形成稳定的酯类化合物。学好数理化，走遍天下都不怕。