Month: November 2020

A common compound: 816-27-3, name is Ethyl 2-ethoxy-2-iminoacetate, belongs to esters-buliding-blocks compound, it can change the direction of chemical reaction, and react with certain compounds to generate new functional products. A new synthetic method of this compound is introduced below. 816-27-3

(3) A mixture of ethyl 2-imino-2-ethoxyacetate (60 g) (purity 78.8%) and ammonium chloride (17.4 g) in methanol (180 ml) was stirred for 3 hours at room temperature and cooled to -15 to -10 C. To the resulting mixture containing 1-methoxycarbonylformamidine hydrochloride were dropwise added bromine (51.2 g) over a period of 10 minutes, triethylamine (71.1 g) over a period of 30 minutes and a solution of potassium thiocyanate (31.0 g) in methanol (150 ml) over a period of 30 minutes. The resulting mixture was stirred at -10 to -5 C. for 15 minutes and at 0 to 5 C. for an additional 1.5 hours. Precipitates were collected by filtration, washed with methanol and thereto was added cold water (200 ml). The mixture was stirred and the precipitates were collected by filtration, washed with cold water and dried to give methyl 5-amino-1,2,4-thiadiazole-3-carboxylate (32.5 g).

In the field of chemistry, the synthetic routes of compounds are constantly being developed and updated. I will also mention this compound in other articles, 816-27-3, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; Fujisawa Pharmaceutical Co., Ltd.; US4390534; (1983); A;,
Ester – Wikipedia,
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83-27-2, Each compound has different characteristics, and only by selecting the characteristics of the compound suitable for a specific situation can the compound be applied on a large scale. 83-27-2, name is Diethyl 2-(sec-butyl)malonate, This compound has unique chemical properties. The synthetic route is as follows.

STEP A: 1-(3,4-dichlorophenyl)-4-(sec-butyl)-pyrazolidine-3,5-dione 50 g of 3,4-dichlorophenylhydrazine (85%) and 122.5 g of diethyl sec-butyl-malonate were heated for 10 hours at 180 C. (external temperature) while distilling 21.3 g of ethanol. The remainder was taken up in 200 ml of methylene chloride, and the solution was extracted with 2N sodium hydroxide, then with water. The combined aqueous phases were washed with methylene chloride and acidified to pH 1 by concentrated hydrochloric acid. The precipitate was separated, washed with water, separated, dried under reduced pressure at 40 C. to obtain 64.8 g of 1-(3,4-dichlorophenyl)-4-(sec-butyl)-pyrazolidine-3,5-dione melting at 118-120 C.

If you are interested in these compounds, you can also browse my other articles.Thank you for taking the time to read this article. I hope you enjoyed it.

Reference:
Patent; Roussel Uclaf; US4808210; (1989); A;,
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

18013-97-3, name is Diethyl 2,5-dibromoterephthalate, 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. 18013-97-3

In a 100 mL Schlenck tube, tin hydride material a1′ (4.7 g) and brominated material b1′ (2.8 g) were successively added.Pd(PPh3)4 (890 mg), toluene (50 mL),Under nitrogen protection, heated under reflux for 40 hours,After removing the toluene by vacuum evaporation and passing through the silica gel column,Dichloromethane as eluent gave the product c1′ (2.5 g, yield 74%) as a yellow solid.

Statistics shows that 18013-97-3 is playing an increasingly important role. we look forward to future research findings about Diethyl 2,5-dibromoterephthalate.

Reference:
Patent; (31 pag.)CN107652304; (2018); A;,
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

As we all know, there are many different methods for the synthesis of a compound, and people can choose the synthesis method that suits their own laboratory according to the actual situation. 3469-00-9 name is Methyl Diphenylacetate, This compound is widely used in many fields, so it is necessary to find a new synthetic route. The downstream synthesis method of this compound is introduced below. 3469-00-9

2.1 Methyl 2-(cyclohex-2-enyl)-2,2-diphenylacetate (1) Lithium di-isopropylamide (LDA) was generated in situ by slow addition of n-BuLi (1.65 mL, 1.6 mol/L, 2.65 mmol, 1.3 equiv.) to the solution of di-isopropylamine (371 mg, 2.87 mmol, 1.2 equiv.) in THF (4 mL) and stirred for 0.5 h at -78 C. Methyl diphenylacetate (500 mg, 2.21 mmol) in THF (5 mL) was added slowly over 1 h at the same temperature and stirred for an additional 1 h. 3-Bromocyclohexene (391.3 mg, 2.431 mmol, 1.1 equiv.) was added slowly to the reaction mixture, allowed to warm up at room temperature freely and stirred for 24 h. Quenched with aqueous HCl (5 mL, 1 mol/L), stirred and partitioned between H2O (10 mL) and CH2Cl2 (3 *20 mL), the organic layer was combined, dried over anhydrous Na2SO4, filtered, concentrated under reduced pressure and purified by column chromatography with EtOAc/n-hexane (1/20, v/v) afforded 1 as a clear colorless oil (500 mg, 86%) which was crystallized from n-hexane. 1H NMR (400 MHz, CDCl3): delta 7.29-7.26 (m, 10 H, 2Ph-H), 5.67-5.62 (m, 2H, 2′,3′-H), 3.81 (m, 1H, 2-H), 3.62 (s, 3H, Me), 1.88-1.01 (m, 6H, 4′,5′,6′-H).

At the same time, in my other blogs, there are other synthetic methods of this type of compound, Methyl Diphenylacetate, and friends who are interested can also refer to it.

Reference:
Article; Sohail, Muhammad; Wang, Yao-Feng; Wu, Shao-Xiang; Zeng, Wei; Guo, Ji-Yi; Chen, Fu-Xue; Chinese Chemical Letters; vol. 24; 8; (2013); p. 695 – 698;,
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

59247-47-1, These common heterocyclic compound, 59247-47-1, name is tert-Butyl 4-bromobenzoate, 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.

To a 25 mL sealed tube was added 5-[[5-cyclopropyl-3-(2,6-dichlorophenyl)-L2-oxazol-4-yl]methoxy ]-3-methyl-2-azabicydo[2.2.l]heptane trifluoroacetic acid salt 360m(250 mg, 0.49 mmol, 1.00 equiv.), tert-buty 4-bromobenzoate (196 mg, 0.76 mmol, 1.5010 equiv.), Ruphos precatalyst (lOS rng, 0.20 equiv ), Ruphos (59.5 mg, 0.20 equiv.), tol (6 mL),and Cs2CCh (595 mg, 1.83 mmol, 3.00 equiv.). The resulting mixture was heated at 110 ¡ãCovernight. After cooling to room temperature, f-hO (l 00 mL) was added, the mixture wasextracted ¡¤with ethyl acetate (lOO mL x 2). The combined organic extracts vvere washed withbrine (200 mL x 2), dried over anhydrous sodium sulfate, and concentrated under vacuum15 The residue was purified by silica gel column chromatography eluting with ethylacetate/petroleum ether (1:3) to give tert-butyl 4-(5-[[5-cydopropyl-3-(2,6-dichloropheny l)-1 ,2-oxazol-4-yl]methoxy]-3-methyl-2-azabicyclo[2.2.l ]hept:m-2-yl)benzoate 360n (230 mg,81 percent) as a light yellow foam

Chemical properties determine the actual use. Each compound has specific chemical properties and uses. We look forward to more synthetic routes in the future to expand reaction routes of 59247-47-1.

Reference:
Patent; ARDELYX, INC.; CHAO, Jianhua; JAIN, Rakesh; HU, Lily; LEWIS, Jason Gustaf; BARIBAULT, Helene; CALDWELL, Jeremy; (582 pag.)WO2018/39386; (2018); A1;,
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

609-12-1, 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 609-12-1 as follows.

[00281] 3-Methyl-2-(2-methyl-1H-indol-4-yloxy)-butyric acid ethyl ester (2): A mixture of 4-hydroxy-2-methylindole (1) (1.5 g, 0.010 mole), 2-bromo-3-methyl-butyric acid ethyl ester (2.2 g, 0.010 mole) and potassium carbonate (excess) in acetone (50 mL) was refluxed for 3 days. The reaction mixture was filtered, and the filtrate was concentrated. The residue was purified by column chromatography (20:1 Hex:EtOAc) to afford intermediate 2. Yield: 1.88 g, 71 %

According to the analysis of related databases, Ethyl 2-bromo-3-methylbutanoate, the application of this compound in the production field has become more and more popular.

Reference:
Patent; ILYPSA, INC.; WO2007/56280; (2007); A1;,
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

34846-90-7, Name is Methyl 3-methoxyacrylate, 34846-90-7, 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.

To three reaction bottles were added 10.8 g (100 mmol) of phenylhydrazine, 11.6 g (100 mmol) of methyl methacrylate,100 mL of methanol. The temperature of the reaction mixture was raised to reflux for about 6 hours. The reaction liquid was quantified by liquid chromatography, and 1-phenyl-5-hydroxypyrazoleYield 85.7percent.

Statistics shows that Methyl 3-methoxyacrylate is playing an increasingly important role. we look forward to future research findings about 34846-90-7.

Reference:
Patent; Hunan Haili Changde Agrochemical Co.,Ltd.; Hu, Zhibin; Liu, Weidong; Du, Shenghua; Huang, Chaoqun; Lan, Shilin; Xiong, Lili; Wu, Yinyin; Cheng, Chao; Wang, Yanli; (6 pag.)CN104059020; (2016); B;,
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

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 61644-18-6 as follows. 61644-18-6

Example 6 Isobutyroxymethyl methyl 4-(2′,3′-dichlorophenyl)-2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate To a stirred mixture of 1,4-dihydro-2,6-dimethyl-4-(2′,3′-dichorophenyl)-5-carboxymethyl-3-pyridinecarboxylic acid (5.11 g, 14 mmol) and sodium bicarbonate (2.39 g, 28 mmol) in DMF (250 ml) under argon atmosphere was added chloromethyl isobutyrate (2.93 g, 21 mmol). The reaction mixture was heated for 80 C. for 18 h. Workup by evaporation of solvent. The crude residue was dissolved in dichloromethane and washed with sodium bicarbonate-solution. The organic layer was dried and evaporated. The residue was chromatographed on silica gel by gradient eluation (dichloromethane to 25% ethyl acetate in dichloromethane). Recrystallization from diisopropylether gave colorless crystals (3.35, 52%), mp. 145 C. 1 H-NMR (CDCl3): 7.30-7.04 (m, 3H); 5.73 (d, J=5.5 Hz, 1H); 5.71 (d, J=5.5 Hz, 1H); 5.68 (s, 1H); 5.47 (s, 1 H); 3.60 (s, 3H); 2.49 (m, 1 H); 2.33 (s, 3H); 2.31 (s, 3H); 1.10 (m, 6H). 13 C-NMR (CDCI3): 175.66; 167.62; 165.77; 147.44; 146.47; 143.78; 132.97; 131.24; 129.81; 128.33; 126.93; 103.99; 102.06; 78.89; 50.86; 38.63; 33.69; 19.83; 19.22; 18.55.

According to the analysis of related databases, 61644-18-6, the application of this compound in the production field has become more and more popular.

Reference:
Patent; Astra Aktiebolag; US5856346; (1999); A;,
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

57381-43-8, Adding a certain compound to certain chemical reactions, such as: 57381-43-8, name is Methyl 2,5-dibromobenzoate, belongs to esters-buliding-blocks compound, can increase the reaction rate and produce products with better performance than those obtained under traditional synthetic methods. Here is a downstream synthesis route of the compound 57381-43-8.

[150] To a dried 25 mL flask was introduced 3-tert-butyl-1-(2-methylphenyl)-1H-pyrazol- 5-amine (intermediate C, 220 mg, 0.96 MMOL), methyl 2,5-dibromobenzoate (235 mg, 0.80 MMOL), Pd2 (dba) 3 (36.6 mg, 0.04 MMOL), BINAP (49.8 mg, 0.08 MMOL), and CS2CO3 (365 mg, 1.12 MMOL). The flask was degassed followed by addition of toluene (1 mL), and the mixture was then heated to 110¡ãC for 20 h. The mixture was cooled to rt, and diluted with ethyl acetate. The solid was filtered off, and the solvent was removed under reduced pressure. The residue was redissolved in METHANOL/THF (4: 1, V/V) and filtered though a CB-SILICA plug. HPLC purification using a gradient elution from 10percent to 90percent acetonitrile in water afforded 110 MG (31 percent) of the TITLE COMPOUND.APOS;H NMR (300 MHZ, CD2CI2) 5 9.21 (s, 1 H), 7.41 (d, 1 H), 7.20-7. 30 (m, 5 H), 7.10 (d, 1 H), 6.09 (s, 1 H), 3.72 (s, 3 H), 2.04 (s, 3 H), 1.30 (s, 9 H). ES-MS M/Z 444.1 (MH+) ; HPLC RT (min) 4.30.

In the field of chemistry, the synthetic routes of compounds are constantly being developed and updated. I will also mention this compound in other articles, Methyl 2,5-dibromobenzoate, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; BAYER PHARMACEUTICALS CORPORATION; WO2004/50650; (2004); A1;,
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Adding some certain compound to certain chemical reactions, such as: 14062-25-0, name is Ethyl 2-(4-bromophenyl)acetate, can increase the reaction rate and produce products with better performance than those obtained under traditional synthetic methods. Here is a downstream synthesis route of the compound 14062-25-0. 14062-25-0

(4-bromophenyl)-acetic acid ethyl ester (0.1 g, 0.41 mmol) was dissolved in 1 mLof THF. t-BuOK (0.092 g,0.82 mmol) was added thereto, and iodomethane (0.051 mL, 0.82 mmol) was added thereto at 0C. The mixture wasstirred at room temperature for 18 hours. After addition of 1N HCl and water, the reaction solution was extracted withEtOAc. The organic layer was separated, dried with MgSO4 and purified by column chromatography to obtain the titlecompound (0.047 g, 42%).1H-NMR (CDCl3) delta 7.42 (2H, d), 7.21 (2H, d), 4.11 (2H, q), 1.54 (6H, s), 1.18 (3H, t).

Chemical properties determine the actual use. Each compound has specific chemical properties and uses. We look forward to more synthetic routes in the future to expand reaction routes of Ethyl 2-(4-bromophenyl)acetate.

Reference:
Patent; LG Chem, Ltd.; KIM, Young Kwan; PARK, Sang Yun; JOO, Hyun Woo; CHOI, Eun Sil; PAEK, Seung Yup; KANG, Seung Wan; KIM, Byung Gyu; LEE, Chang Seok; KIM, Sung Wook; LEE, Sang Dae; (369 pag.)EP3239143; (2017); A2;,
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics