羧酸（或盐）和硫酸酯、磺酸酯酯化的示例：

     2-Hydroxy-1-naphthoic acid (470.5 mg, 2.5 mmol) in dry THF (2.5 mL) was treated with LiOH.H2O (104.9 g, 2.5 mol) at room temperature for 30 min followed with Me2SO4 (0.24 mL, 2.5 mol), and the mixture was heated for 3 h. Solvent was distilled off, and the mixture was diluted with saturated aqueous NaHCO3 and the extracted with Et 2 O to afford the ester (485.16 mg, 96%) as a white solid。

     Trethyl orthoacetate (16.0 mL, 87 mmol) was added dropwise to a solution of 1-naphthoic acid (5.0 g, 29 mmol) in toluene (35 mL). The reaction mixture was heated at reflux for 24 h. After the mixture has cooled, 2 N HCl (30 mL) was added. The organic extract was washed with saturated NaHCO 3 (30 mL) and brine (30 mL) and dried with MgSO 4 . The solvent was removed in cacuo to give a brown oil.Kugelrohr distillation of the product at 100℃ (0.45 Torr) gives the ethyl ester (5.15 g,89%)。

 酸酐和醇、酚的酯化反应示例：

      酸酐的酰化能力很强，当加入少量的（几滴）硫酸催化反应能在很短的时间内完成，几乎是定量的。反应中，催化剂硫酸提供质子，酸酐接受质子形成酰基正离子，与醇、酚完成酰化反应后又释出质子。

      To the above flask, containing 3-nitro-4-hexanol (330 g, 2.24 mol) was added a magnetic stirring egg and 1 mL of conc. sulfuric acid. The contents of the flask were stirred in an ice bath and acetic anhydride (240 g, 2.35 mol) was added in portions, keeping the temperature of the reactants below 60 ℃ . After the addition of the acetic anhydride was complete, the contents of the flask were stirred for 1 h. The flask was then equipped for vacuum distillation. The lower boiling components (Ac2O and AcOH) were removed at 25 mm by gently heating the stirred contents of the flask (≤100 ℃ bath temperature). After these reagents have been removed, the system was cooled, attached to a vacuum pump, and carefully heated. The fraction boiling at 105–107 ℃/10 mm was collected, affording 4-acetoxy-3-nitrohexane (379 g, 90%)。

      In a 1000mL flask, the nitrodiol (52 g, 0.323 mol) were suspended in acetic anhydride (150 mL). Without cooling, 3~6 drops of concentrated sulfuric acid were added. After stirring for 1 h, 500 mL of ice/water was rapidly added and stirring was continued for 60 min. The resulting colorless crystals were filtered, washed with water, and air-dried to give the product (75.6 g, 95.6%) of colorless crystals。

     5-Hydroxywasophthalic acid (360.56 g, 1.98 mol) was charged to a 2000 mL round bottom 3-neck flask with a Friedrich condenser and thermocouple under a blanket of nitrogen. Acetic anhydride (808.25 g, 7.96 mol) was added slowly. The white suspension was stirred and refluxed (~136℃) for 4 h. After cooling the white solid was filtered off and washed with toluene to afford 5-acetoxywasophthalic acid (336.95 g, 76%)

     294 ml of butyric acid anhydride was treated with addition of 2 ml of concentrated aqueous sulfuric acid at room temperature, and then 122 g of 3,5-dimethyl-phenol was added to the solution at room temperature. The reaction temperature raised to 40℃ and was then raised to 80℃. The mixture was stirred for 1 h and diluted with 60 mL of water and 60 mL of ethanol, poured onto ice water and twice extracted with 500 mL of hexane each time. The hexane extract was washed with water, aqueous sodium bicarbonate solution, dried over sodium sulfate and evaporated to give butyryloxy-3, 5-dimethyl-benzene which boils at 123℃.-125℃/11 mm Hg after rectification。

 酰氯和醇、酚的酯化反应示例：

       酰氯是强酰化剂和醇、酚作用生成酯的反应很迅速，此方法适用于由空间障碍的酯化。经常是在吡啶或其它叔胺参与下反应。

    In an oven-dried, 500-mL, two-necked, round-bottomed flask equipped with a magnetic stir bar and a rubber septum was placed ,3,5-tri-O-benzoyl-α-D-ribofuranose (5.0 g, 10.8 mmol) and 2,6 lutidine (1.4 g, 13.0mmol) in 200 mL of dry dichloromethane under an argon atmosphere. The reaction mixture was cooled to 0 ℃ and 3-(trifluoromethyl)benzoyl chloride (3.3 g, 16.2 mmol) was added dropwise to the stirred solution over 30 min. After the addition, the reaction mixture was warmed to room temperature and stirred overnight. The reaction was quenched with 80 mL of aqueous saturated sodium bicarbonate, the phases were separated and the aqueous phase was extracted with dichloromethane (200 mL × 2). The combined organic extracts were washed with brine (100 mL × 2) and dried over anhydrous magnesium sulfate. After filtration, the solvent was removed under reduced pressure to give yellow oil. Purification by flash column chromatography (140 g of silica gel) and eluting with 25% ethyl acetate in hexanes gives a white solid that can be recrystallized from EtOAc/hexane to yield 1,3,5-O-tribenzoyl-2-O[(3-

trifluoromethyl)benzoyl]- -α-D-ribofuranose (5.62 g, 82%) as white crystals。

    A mixture of 28.5 g of 4-nitrobenzoyl chloride, 30.0 g of 3,5-dichlorophenol and 300 mL of pyridine was heated under reflux for 3 h. After completion of the reaction, the pyridine was distilled off under reduced pressure, the remaining reaction product was dissolved in ethyl acetate, and the solution was washed with water and then with a

saturated aqueous solution of sodium chloride and concentrated under reduced pressure to give crude crystals, which was recrystallized from ethyl acetate to give 3,5-dichlorophenyl-4-nitrobenzoate (44.2 g) as needles 。

   To the mixture of 3-Hydroxy-5-pregn-16-en-20-one (10 g) in pyridine (50 mL) was added p-methylbenzenesulfonyl chloride (10 g), and the reaction mixture was stirred at room temperature overnight and then poured into dilute hydrochloric acid. The precipitate was extracted into chloroform, and the extract was washed with dilute hydrochloric acid and with water, dried over sodium sulphate and evaporated to an oil which crystallized on standing. Recrystallisation from ethyl acetate/petrol gave 3-p-methylbenzenesulfonyloxy-5-pregn-16-en-20-one (13.3 g) as off-white prisms。

 酯交换的反应示例：

      酯和另一种过量的醇在少量的碱或酸催化下共热，发生烷氧基转移，生成另一种酯。

      A mixture of Ethyl 2-cyano-3,3-diphenylacrylate (83.1 g，0.3 mol), cyclopentanol(100 mL) and Na 2 CO 3 (6 g) were heated at 145℃ with disstillative removal of the ethanol formed, assisted by a stream of nitrogen. After about 3 h, the reaction mixture was filtered hot in order to remove the Na 2 CO 3 . After the filtrate had been cooled, the precipitate which had formed was filtered off, washed with petroleum ether and dried to give cyclopentyl 2-cyano-3, 3-diphenylacrylate (78.1 g, 82%) as a colorless solid。

   The mixture of 500 mg of 3-acetyloxy-7-[(5-nitro-2-pyridinyl)oxy]-1H-indene, 5 ml of benzoyl chloride and 15 mg of p-toluenesulfonic acid was stirred at 100℃. After stirring for 1.5 h, ethyl acetate was added to the reaction solution and the solution was washed in turn with a saturated sodium hydrogencarbonate solution and a saturated sodium chloride solution. The solution extracted with ethyl acetate was dried over anhydrous magnesium sulfate and the solvent was distilled off. The resulting residue was purified by silica gel column chromatography (eluent: hexane/ethyl acetate=10:1) to obtain 130 mg of 3-benzoyloxy-7- [(5-nitro-2-pyridinyl) oxy]-1H-indene as a white powder

   A solution of 6-acetoxycholestan-3-one (1.215 g, 2.74 mmol) of isopropenyl acetate (15 mL) was refluxed in the presence of p-toluenesulfonic acid (20 mg) under argon for 3 h. Most of the solvent was removed and the concentrated mixture was extracted with ethyl acetate. The extract was washed with saturated NaHCO 3 , and brine, and dried over MgSO 4 . The residue obtained upon evaporation of the solvent was purified、by column chromatography on silica gel (40 g) to give 2,6-Diacetoxycholest-2-ene (1.265 g, 95%) 

   5-Hexynoic acid (26.9 mg), 40.6 mg of 2-chloro-1, 3-dimethylimidazolinium chloride and 37.9 mg of pyridine were stirred in dichloromethane (10 mL) at room temperature for one h. Thereafter, 50 mg of 2,3-dimethyl-4-hydroxy-5, 6-difluoroquinoline was added thereto, and the mixture was stirred at room temperature for 15 h. Water was added to the reaction solution, and the mixture was extracted with dichloromethane. The dichloromethane layer obtained was washed with a saturated aqueous sodium hydrogencarbonate solution and was then dried over anhydrous sodium sulfate. The solvent was then removed by evaporation under the reduced pressure. The crude product thus obtained was purified on Wako Gel C-200 (10 g; elution solvent: hexane/EtOAc=10:1) to give 77.8 mg of 2,3-dimethyl-4- (5-hexynoylcarbonyloxy)-5,6-fluroq uinoline 

      To the solution of Biotin (1.0 g, 4.1 mmol) in 20 mL of DMF, triethylamine (1 mL, 8 mmol) was added followed by the addition of 2,3,5,6-tetrafhtororophenyl trifluoroacetate (1.76 g, 1 mmol) under argon atmosphere at 25℃. The reaction mixture was stirred at room temperature for 30 min and the solvent was removed under vacuum. The product was triturated in 10 mL of ether and filtered. The isolated

product was dried under vacuum to yield biotin TFP ester (1.3 g, 80%) as a colorless solid 

 腈的醇解反应示例：

      在酸催化下，氰基可以醇解直接生成酯。通常使用的催化剂是浓硫酸或氯化氢，只适用于伯醇，因为叔醇和仲醇在硫酸作用下会生成烯，硫酸和释放出的氨成盐。腈的醇解，醇兼作溶剂，其用量比较大，一般是理论量的 4～5 倍；硫酸的用量也要超过理论用量的 0.5～1 倍。

    1-(4-Cyanophenyl)-piperazine (11 mmol) was dissolved in 5 N a solution of concentrated sulfonic acid and methanol (15 ml) and stirred in a sealed tube at 110℃ for 3 h. After evaporation of the solvent, the residue was dissolved in water and extracted with ethyl acetate. Addition of sodium carbonate to the water phase until pH 9 results in the precipitation of a white solid which was filtered off and dried (vacuum). A white powder with R f 0.59 (CH 2 Cl 2 /MeOH = 9:1) was obtained. 4-piperazin-1-yl-benzoic acid methyl ester

    1-[2,2-Bis(4-cyanobenzylthio)ethyl]-1H-imidazole hydrochloride (1.43 g) was added to methanol (50 mL) which had been saturated with hydrogen chloride at 0℃. The resulting solution was stirred under reflux for 20 h and then concentrated. The gummy residue was partitioned between CH 2 Cl 2 and aqueous NaHCO 3 , and the CH 2 Cl 2 layer was washed with brine and dried over Na 2 SO 4 . Removal of the CH 2 Cl 2 left a gum which was hromatographed on silicic acid (60 g) with CH 2 Cl 2 /CH 3 OH (95:5), to afford 1.1 g of the free base of the title compound as a viscous oil. Treatment of a solution of the base in CH 3 OH-ether with hydrogen chloride provided colorless crystals of 1-[2,2-Bis(4-carbomethoxybenzylthio)ethyl]-1H-imidazole

Hydrochloride 。

 其他酯化反应示例：

   3-(2,2-Diethoxyethoxy)-5-chlorophenol (0.05 mole) dissolved in benzene (10 ml) was charged into a glass reaction flask equipped with a mechanical stirrer. Phenyl isocyanate (0.06 mole) and triethylamine (3 drops) were then added, and the resulting mixture was stirred at room temperature for a period of about 6 hours. The mixture was then stripped of solvent and unreacted isocyanate to yield the desired productO-[3-(2,2-diethoxyethoxy)-5-chlorophenyl]N-phenylcarbamate as the residue 。

     A 500-mL, one-necked flask equipped with a calcium chloride drying tube was charged with 28.83 g (0.20 mol) of monoethyl fumarate, 200 mL of dry dichloromethane, 44.47 g (0.60 mol) of tert-butyl alcohol, and 2.00 g (0.16 mol) of 4-dimethylaminopyridine. The solution was stirred and cooled in an ice bath to 0°C while 45.59 g (0.22 mol) of dicyclohexylcarbodiimide was added over a 5-min period.

After a further 5 min at 0°C the ice bath was removed and the dark-brown reaction mixture was stirred for 3 h at room temperature. The dicyclohexylurea that has precipitated was removed by filtration through a fritted Büchner funnel (G3), and the filtrate was washed with two 50-mL portions of 0.5 N hydrochloric acid and two 50 mL portions of saturated sodium bicarbonate solution. During this procedure some

additional dicyclohexylurea was precipitated, which was removed by filtration of both layers to facilitate their separation. The organic solution was dried over anhydrous sodium sulfate and concentrated with a rotary evaporator. The concentrate was distilled under reduced pressure, affording after a small forerun, 30.5–32.5 (76–81%) of tert-butyl ethyl fumarate, bp 105–107°C (12 mm)