Esters-buliding-blocks

2555-28-4,Some common heterocyclic compound, 2555-28-4, name is 7-Methoxy-4-methylcoumarin, molecular formula is C11H10O3, traditional synthetic route has been very mature, but the traditional synthetic route has various shortcomings, such as complicated route, low yield, poor purity, etc, below Introduce a new synthetic route.

(0.95 g, 5 mmol) of 4a, 50 mL of xylene was added to a round bottom flask,Stir and heat, so that it gradually dissolved.Then, selenium dioxide (0.55 g, 5 mmol) was added and the reaction was refluxed for 12 h.Stop heating, hot suction filter, the filtrate cold with yellow solid precipitation, The filtrate was concentrated under reduced pressure to give a yellow solid 4b (0.85 g, yield 84%).

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 2555-28-4, its application will become more common.

Reference:
Patent; Shandong He Bentang Biological Technology Co., Ltd.; Pan Xuan; Zhang Chengrui; Wang Huili; (9 pag.)CN106317029; (2017); A;,
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A common heterocyclic compound, 35180-01-9, name is Chloromethyl isopropyl carbonate, molecular formula is C5H9ClO3, its traditional synthetic route has been very mature, but the traditional synthetic route has various shortcomings, such as complicated route, low yield, poor purity, etc, below Introduce a new synthetic route. 35180-01-9.

S03 condensation: After pretreating the crude tenofovir obtained in the step S02, and stirring 16 L of N-methylpyrrolidone and 4.44 kg of triethylamine, the temperature is raised to 50 C and stirred.11.15 kg of isopropyl chloromethyl carbonate was added dropwise, stirred, and the reaction was completely cooled and quenched.After cooling, add 12 L of cyclohexane twice, stir, centrifuge, layer, and discard the upper layer of cyclohexane. The lower layer of the filtrate was transferred to a reaction kettle, and 30 L of water and 20 L of ethyl acetate were added.After stirring for 30 minutes, the layers were allowed to stand, and the aqueous layer was extracted with 10 L of ethyl acetate.Wash with 20L of 10wt% brine, add 1.0kg anhydrous sodium sulfate, stir dry, centrifuge,The filtrate is transferred to the transfer reactor in batches, concentrated under reduced pressure, and the concentrate is transferred to the reaction vessel.Denotefovir dipivoxilCrude.

The synthetic route of Chloromethyl isopropyl carbonate has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Shandong Kexing Biological Products Co., Ltd.; Hao Zhihai; Wang Cuicui; Lu Fuxin; Guo Chao; Wang Jun; Zhang Yun; Qiu Duxian; Cui Ning; (26 pag.)CN108409789; (2018); A;,
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The chemical industry reduces the impact on the environment during synthesis 139102-34-4, name is Methyl 4-bromo-2-methoxybenzoate, I believe this compound will play a more active role in future production and life. 139102-34-4

Preparation of Example 389; Step i:; To methyl-4-bromo-2-methoxybenzoate (Aldrich) (1.0 g, 4.1 mmol) in THF(10 ml_), was added LiBH4 (0.13 g, 6.1 mmol). Ethanol (2 mL) was added dropwise. The resulting reaction mixture was stirred at room temperature for 20 h. 1 N NaOH was added, and the mixture was extracted with EtOAc. The organic layers were combined and washed with water and brine, then dried (MgSO4), filtered, and concentrated in vacuoXo provide the corresponfing benzyl alcohol (0.86 g, 4.0 mmol).

The chemical industry reduces the impact on the environment during synthesis 139102-34-4. I believe this compound will play a more active role in future production and life.

Reference:
Patent; SCHERING CORPORATION; WO2006/60461; (2006); A1;,
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Some common heterocyclic compound, 4341-76-8, name is Ethyl 2-butynoate, molecular formula is C6H8O2, traditional synthetic route has been very mature, but the traditional synthetic route has various shortcomings, such as complicated route, low yield, poor purity, etc, below Introduce a new synthetic route. 4341-76-8

General procedure: In a two neck rbf was stirred a mixture of Pd(OAc)2 (275 mg,1.22 mmol) and TDMPP (540 mg, 1.22 mmol) in benzene (30 ml)for 15 min at rt under nitrogen. To this mixture was added ethyl-2-butynoate 7 (2.84 ml, 24.48 mmol) and the resulting mixturewas further stirred for 10 min at rt. Next, ethynylbenzene 4a(2.50 g, 24.48 mmol) was added to this solution and the mixturewas stirred for 5-10 min until reaction was completed. Theworkup of reaction was performed by evaporating the solvent invacuum followed by column chromatography (Hexane:EtOAc = 100:1) to give the desired compound 8a (2.62 g);

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 4341-76-8, its application will become more common.

Reference:
Article; Singh, Sarbjit; Goo, Ja-Il; Noh, Hyojin; Lee, Sung Jae; Kim, Myoung Woo; Park, Hyejun; Jalani, Hitesh B.; Lee, Kyeong; Kim, Chunsook; Kim, Won-Ki; Ju, Chung; Choi, Yongseok; Bioorganic and Medicinal Chemistry; vol. 25; 4; (2017); p. 1394 – 1405;,
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3196-15-4, Name is Methyl 2-bromobutyrate, 3196-15-4, belongs to esters-buliding-blocks compound, is considered to be a conventional heterocyclic compound, which is widely used in drug synthesis. The chemical synthesis route is as follows.

Example 1. Synthesis of benzo bis-furan compound IV-1 (1) In a round-bottom flask equiped with a reflux condenser and a magnetic stirrer, 0.5135g (1.0mmol) of compound I dissolved in 10mL DMF and 0.346g (2.5mmol) potassium carbonate was added. The reaction was stirred at room temperature. After ten minutes, 0.272g (1.5mmol) 2-bromobutyric acid methyl ester VI-a-1 was added and stirring was continued for 5h. After completion of the reaction, 30mL of dichloromethane was added with copious amount of water (80mL¡Á5) until removal of DMF. The organic phase was seperated, dried over anhydrous magnesium sulfate, concentrated, and purified by TLC (E/P [ethyl acetate:petroleum ether] = 1:5) to give the benzofuran II-a-1. Yield 75%

Statistics shows that Methyl 2-bromobutyrate is playing an increasingly important role. we look forward to future research findings about 3196-15-4.

Reference:
Patent; Zhejiang University; Wang, Yuguang; Zhu, Bingchun; Liu, Juanfang; Li, Qingsi; (14 pag.)CN104016998; (2016); B;,
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A common heterocyclic compound, 178312-47-5, name is Ethyl 4,4-difluorocyclohexanecarboxylate, molecular formula is C9H14F2O2, its traditional synthetic route has been very mature, but the traditional synthetic route has various shortcomings, such as complicated route, low yield, poor purity, etc, below Introduce a new synthetic route. 178312-47-5.

Synthesis of Compound 349: To a solution of the ethyl ester (349A; 10 g; 0.052 mol.) in diethyl ether (50 ml) at-78 C (bath temp. ) was added KHMDS (0.5 M in toluene ; 156.087 ml ; 1.5 equiv. ). The resulting solution was stirred for 30 minutes, then benzyl chloromethyl ether (11.89 ml ; density 1.13 ; 1.65 equiv. ) was added. The reaction mixture was stirred at-78 C to R. T. for 24 h. Reaction was stopped by addition of saturated aq. NH4C). It was then diluted with ethyl acetate and the combined organic phase was washed with brine, dried over Na2SO4 and evaporated to dryness in vacuo to provide a light brown oil (24.2 g). It was chromatographed over silica gel (300 g). The column was eluted with 1 %- 4% ethyl acetate in n-hexane providing in some of the fractions pure 349B (6.54 g).

The synthetic route of Ethyl 4,4-difluorocyclohexanecarboxylate has been constantly updated, and we look forward to future research findings.

Reference:
Patent; SCHERING CORPORATION; WO2005/87731; (2005); A1;,
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46004-37-9, Researchers who often do experiments know that organic synthesis is a process of preparing more complex target molecules from simple raw materials through one or more chemical reactions. Generally, it requires fewer steps, and cheap raw materials. 46004-37-9, name is Methyl 4-amino-2-chlorobenzoate, A new synthetic method of this compound is introduced below.

To a solution of methyl 2-chloro-4-aminobenzoate (109 g, 587 mmol) in 440 mL DMF was added NaIO4 (50 g) and iodine (119 g). The mixture was warmed at 50 C. for 2 h. It was then cooled and diluted with water and filtered. The solid was treated with sodium hydrogensulfite (19 g) in water (110 mL) at 40 C. for 1 h. The mix was filtered again and washed with water, followed by isopropanol. Upon drying, the product was obtained in 56% yield. M+H+(312).

The basis of chemical reaction formula synthesis, the synthesis route is composed of some specific reactions and combined according to certain logical thinking. We look forward to the emergence of more reaction modes in the future.

Reference:
Patent; Chakravarty, Sarvajit; Dugar, Sundeep; Lu, Qing; Luedtke, Gregory R.; Mavunkel, Babu J.; Perumattam, John J.; Tester, Richland W.; US2004/142940; (2004); A1;,
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106-32-1,Some common heterocyclic compound, 106-32-1, name is Ethyl octanoate, molecular formula is C10H20O2, traditional synthetic route has been very mature, but the traditional synthetic route has various shortcomings, such as complicated route, low yield, poor purity, etc, below Introduce a new synthetic route.

General procedure: To a solution of 1,1,2,2,3,3,4,4,5,5,6,6,6-tridecafluorohexyl iodide (0.22 mL, 1.0 mmol), ethyl benzoate (0.16 mL, 1.1 mmol) in Et2O (3 mL) was added at -80C methyllithium (1.5 M in Et2O with lithium bromide; 0.73 mL, 1.1 mmol) and stirring was continued for 30 min at the same temperature where diethyl-aluminium chloride (1 M in n-hexane; 1.1 mL, 1.1 mmol) was gradually added and further stirring for 15 min at -80 C. In a separate flask, lithium bromide (0.12 g, 1.4 mmol), triethyl phosphonoacetate (0.26 mL, 1.3 mmol), and THF (1 mL) was mixed at 0 C where triethylamine (0.19 mL, 1.4 mmol) was added and the solution was stirred for 10 min at room temperature. This mixture was slowly introduced to an aluminium acetal solution prepared above with the aid of cannula and the whole mixture was further stirred for 1 h at room temperature. To this solution were successively added Et2O (3 mL), NaF (0.185 g, 4.4 mmol) and H2O (59 mg, 3.3 mmol), which was stirred for 0.5 h at room temperature. Filtration with a pad of silica gel and concentration furnished a crude mixture which was purified by silica gel column chromatography (n-hexane:CH2Cl2=6:1) to afford 0.484 g (0.979 mmol, 98% yield, E_Z=>99:1) of the title compound 5ca as a colourless oil.

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 106-32-1, its application will become more common.

Reference:
Article; Yamazaki, Takashi; Mano, Noriko; Hikage, Reo; Kaneko, Tsutomu; Kawasaki-Takasuka, Tomoko; Yamada, Shigeyuki; Tetrahedron; vol. 71; 42; (2015); p. 8059 – 8066;,
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In the chemical reaction process, reaction time, type of solvent, can easily affect the result of the reaction, thereby determining the yield and properties of the reaction product. An updated downstream synthesis route of 40546-94-9 as follows. 40546-94-9

A reaction mixture of 0.75 kg 3,4-dihydro-6-methyl -4-phenyl-2H-benzopyran-2-one, 0.262 kg sodium hydroxide and 0.93 L DM water was stirred at 60-650C for 2 hrs. The reaction was cooled to RT. 0.825 kg dimethylsulphate was added drop wise to reaction mixture within 1 hr. After the completion of addition, reaction mixture was stirred at same temperature for 2 hrs. Again solution of 0.186 kg sodium hydroxide in 0.93 L DM water was added at RT within 1 hr. The reaction mixture was stirred at 800C for 4 hrs. After completion of reaction, reaction was cooled to RT. 0.3 L Cone, hydrochloric acid was added drop wise to the reaction mixture till washing is neutral. The reaction mixture was stirred for 2 hrs, then filtered & washed with 2.0 L DM water to obtain wet cake. The wet cake was dried at 60-650C for 10-12 hrs to obtain 3-(2-methoxy-5-methylphenyl)-3-phenyl propionic acid (Yield: 0.71 kg, 83%).[159] HPLC Purity: > 95 %.

According to the analysis of related databases, 40546-94-9, the application of this compound in the production field has become more and more popular.

Reference:
Patent; ALEMBIC LIMITED; PONNAIAH, Ravi; DESAI, Sanjay; SHAH, Chankrakant Chunilal; PATEL, Kalpesh Shantibhai; PAREKH, Viral Maheshbhai; WO2010/46801; (2010); A2;,
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89-91-8, Researchers who often do experiments know that organic synthesis is a process of preparing more complex target molecules from simple raw materials through one or more chemical reactions. Generally, it requires fewer steps, and cheap raw materials. 89-91-8, name is Methyl 2,2-dimethoxyacetate, A new synthetic method of this compound is introduced below.

Step 1 : Preparation of 1-(2,4-dichloropyridin-3-yl)-2,2-dimethoxyethan-1-one . A cold (-78 C) solution of 2,4-dichloro-3-iodopyridine (2.73 g, 9.968 mmol) in THF (49.84 mL) was treated dropwise with 2.5 M n-BuLi in hexanes (4.785 mL, 11.96 mmol). After stirring for 20 min at -78 C, the reaction mixture was treated dropwise with methyl 2,2-dimethoxyacetate (1.708 mL, 13.95 mmol). The resulting mixture was stirred for 1 h at -78 C, before quenching with saturated NH4Cl(aq) (10 mL). The quenched mixture was allowed to warm to ambient temperature. Subsequently, the mixture was diluted with water (30 mL), and extracted with EtOAc. The organic extracts were dried over anhydrous Na2S04(S>, filtered, and concentrated in vacuo. The crude residue was purified by silica chromatography (0-30% EtOAc in hexanes) to afford the title compound (1.9 g, 76%).

The basis of chemical reaction formula synthesis, the synthesis route is composed of some specific reactions and combined according to certain logical thinking. We look forward to the emergence of more reaction modes in the future.

Reference:
Patent; ARRAY BIOPHARMA INC.; WALLS, Shane M.; REN, Li; RAMANN, Ginelle A.; MORENO, David A.; METCALF, Andrew T.; MCFADDIN, Elizabeth A.; KOLAKOWSKI, Gabrielle R.; BLAKE, James F.; DAI, Donghua; HAAS, Julia; JIANG, Yutong; KAHN, Dean; (368 pag.)WO2019/143994; (2019); A1;,
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics