Esters-buliding-blocks

A common heterocyclic compound, 764667-64-3, name is 5-(1-Hydroxy-2-(2,4,5-trifluorophenyl)ethylidene)-2,2-dimethyl-1,3-dioxane-4,6-dione, molecular formula is C14H11F3O5, 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. 764667-64-3.

2,4, 5-TRIFLUOROPHENYLACETIC acid (2-1) (150 g, 0.789 mol), Meldrum’s acid (125 g, 0. 868 mol), and 4- (DIMETHYLAMINO) pyridine (DMAP) (7.7 g, 0063 mol) were charged into a 5 L three-neck flask. N, N-DIMETHYLACETAMIDE (DMAC) (525 ML) was added in one portion at room temperature to dissolve the solids. N, N-diisopropylethylamine (282 ML, 1.62 mol) was added in one portion at room temperature while maintaining the temperature below 40 C. Pivaloyl chloride (107 ML, 0.868 mol) was added dropwise over 1 to 2 h while maintaining the temperature between 0 and 5 C. The reaction mixture was aged at 5 C for 1 h. Triazole hydrochloride 1-4 (180 g, 0.789 mol) was added in one portion at 40-50 C. The reaction solution was aged at 70 C for several h. 5% Aqueous sodium hydrogencarbonate solution (625 ML) was then added dropwise at 20-45 C. The batch was seeded and aged at 20-30 C for 1-2 h. Then an additional 525 mL of 5% aqueous sodium hydrogencarbonate solution was added dropwise over 2-3 h. After aging several h at room temperature, the slurry was cooled to 0-5 C and aged 1 h before filtering the solid. The wet cake was displacement-washed with 20% aqueous DMAC (300 mL), followed by an additional two batches of 20% aqueous DMAC (400 mL), and finally water (400 mL). The cake was suction-dried at room temperature. The isolated yield of final product 2-3 was 89%.

The synthetic route of 5-(1-Hydroxy-2-(2,4,5-trifluorophenyl)ethylidene)-2,2-dimethyl-1,3-dioxane-4,6-dione has been constantly updated, and we look forward to future research findings.

Reference:
Patent; MERCK & CO., INC.; WO2005/20920; (2005); A2;,
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37746-78-4, A common compound: 37746-78-4, name is (E)-Ethyl 4-bromobut-2-enoate, 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.

General procedure: To a vigorously stirring solution of alpha-imino ester 1 (0.5 mmol,1 equiv) and E-ethyl-4-bromocrotonate or methyl-4-bromocrotonate (2, 1.5 mmol, 3 equiv) in EtOH (2 mL) was added indium powder (1 mmol, 2 equiv). The mixture was allowed to stir vigorously for 6 h at 30 C. After this period, the reaction mixturewas quenched with 2 mL of water and transferred to a separating funnel and extracted using ethyl acetate (315 mL). The combined organic layers were dried over anhydrous Na2SO4. Then the solvent was evaporated under vacuum. Purification of the resulting crude reaction mixture by column chromatography on silica gel (EtOAc/Hexane as eluent) gave the product 3 (see Tables 1 and 2 and Scheme 2 for individual entries).

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, (E)-Ethyl 4-bromobut-2-enoate, other downstream synthetic routes, hurry up and to see.

Reference:
Article; Aslam, Nayyar Ahmad; Babu, Srinivasarao Arulananda; Sudha, Arya Jayadev; Yasuda, Makoto; Baba, Akio; Tetrahedron; vol. 69; 32; (2013); p. 6598 – 6611;,
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27007-53-0, A common compound: 27007-53-0, name is Methyl 2-bromo-5-chlorobenzoate, 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.

A solution of 2-bromo-5-chloro-benzoic acid methyl ester Compound 4-2 (5.08 g, 20.4 mmol), the boronate Compound 4-1 (6.00 g, 19.4 mmol), PdCl2dppf-CH2Cl2 (1.06 g, 1.30 mmol) and K2CO3 (8.9 g, 58.21 mmol) in DMF and EtOH (4:1, 90 mL) was prepared in a thick walled tube. The mixture was stirred under argon at rt for 5-10 min and the tube was closed and heated at 90 C. for 5 hrs (4-16 hrs for other examples). The mixture was cooled to rt then filtered thru a pad of Celite, washing with EtOAc. The solvent was evaporated and purified by flash chromatography (gradient elution with 5-50% EtOAc in heptane with 0.1% TEA). The desired product Compound 4-3 was isolated as yellow liquid (4.05 g, 60%). 1H NMR (300 MHz, CDCl3) delta 7.82 (d, J=2.2 Hz, 1H), 7.43 (d of d, J=8.2 and 2.2 Hz, 1H), 7.14 (d, J=8.2 Hz, 1H), 5.51 (br s, 1H), 4.02 (br s, 2H), 3.85 (s, 3H), 3.63 (t, J=5.6 Hz, 2H), 2.30 (br s, 2H), 1.50 (s, 9H); MS (ES+) m/z 374.0 (M+Na).

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-bromo-5-chlorobenzoate, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; Ghosh, Shyamali; Kinney, William A.; Lawson, Edward C.; Luci, Diane K.; Maryanoff, Bruce E.; Sommen, Francois Maria; Pan, Yongchun; US2008/39454; (2008); A1;,
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868-72-4,Some common heterocyclic compound, 868-72-4, name is Dimethyl 2,5-dibromohexanedioate, molecular formula is C8H12Br2O4, 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 stirring solution of dimethyl 2,5-dibromohexanedioate (SM) (50 g, 0.15 mol) in toluene:water (150 mL, 2: 1) were added benzyl amine (16 mL, 0.15 mol) and K2CO3 (24 g, 0.18 mol) at room temperature. The reaction mixture was heated to reflux at 110 C and stirred for 4 h. After consumption of the starting material (by TLC), reaction mixture was cooled to room temperature and extracted with diethyl ether (2 x 50 mL). Separated organic layer was dried over anhydrous Na2S04 and concentrated under reduced pressure to obtain compound 1- mixture (39 g, 93%) as liquid. This material was purified by silica gel column chromatography eluting with 20% EtOAc/n-hexane to afford compound 1-Fl (10 g), compound 1-F2 (13 g) and compound 1-Fl and F2 as a mixture (16 g) as liquid. H NMR (500MHz, CDC13): delta 7.32-7.17 (m, 5H), 3.89 (s, 2H), 3.55 (s, 6H), 3.45-3.38 (m, 2H), 2.08- 1.99 (m, 4H). LCMS (m/z): 278.2 [M++l].

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route Dimethyl 2,5-dibromohexanedioate, its application will become more common.

Reference:
Patent; APTINYX INC.; KHAN, Amin, M.; (197 pag.)WO2018/26792; (2018); A1;,
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

These common heterocyclic compound, 426-65-3, name is Ethyl Pentafluoropropionate, 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. 426-65-3

General procedure: Sodium hydride (4.0 g, 100 mmol, 60% dispersion in mineral oil) was placed in a 500mL round-bottom flack and 50 mL of dry hexane was added. The suspension was stirred for a short time with a magnetic stirring bar and kept until the hexane layer became clear (20-30 min). Hexane was cautiously removed with a glass pipette until a wet paste of NaH remained. This procedure was repeated twice. After that, THF (150mL) was added with vigorous stirring. Anhydrous EtOH (0.5 mL) was added in oneportion at 0 C, followed by the dropwise addition of a solution of 2-acetylthiophene (6.3g, 50 mmol, 5.42 mL) and methyl or ethyl ester of the respective perfluorinatedcarboxylic acid (50.5 mmol) in 30 mL of THF. The white suspension rapidly turns pink and then reddish-brown. Caution Hydrogen evolved during the addition and notable effervescence was observed. The rate of addition was maintained to control the evolution of hydrogen; usually the addition takes 60-80 min. When gas evolution ceased, the cooling bath was removed and the reaction mixture was stirred for 5 h. After that, the dark brown solution with a small amount of precipitate was re-cooled to 0 C,10 mL of anhydrous EtOH was added slowly to decompose traces of NaH, and the resulting solution was stirred for 30 min. The solvent was removed by evaporation under reduced pressure (100 Torr, bath temperature 40 C), then EtOAc (40 mL) andsubsequently a mixture of conc. HCl (20 mL) and crushed ice (80 mL) were added tothe residue. The resulting turbid liquid was shaken by hand until two clear layers formed. The organic phase was separated and the aqueous phase was then extracted with EtOAc (3 ¡Á 50 mL). The combined organic fractions were washed with brine (50mL), dried over MgSO4 and evaporated to dryness. The resulting brown oil was distilled in vacuo (2-3 Torr). The main fraction is pure enough. Additional portions of pure diketone can be separated from low-boiling fractions by precipitation as a copper salt. Decomposition should be performed with HCl (procedure A).

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 426-65-3.

Reference:
Article; Taydakov, Ilya V.; Kreshchenova, Yuliya M.; Dolotova, Ekaterina P.; Beilstein Journal of Organic Chemistry; vol. 14; (2018); p. 3106 – 3111;,
Ester – Wikipedia,
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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,
Ester – an overview | ScienceDirect Topics

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