Day: November 18, 2020

The chemical industry reduces the impact on the environment during synthesis 5744-51-4, name is Ethyl 1,5-dimethyl-1H-pyrazole-3-carboxylate, I believe this compound will play a more active role in future production and life. 5744-51-4

LAH (1.05 M in THF, 15.0 kg, 17.4 mol) was gradually added to a stirring solution of ethyl 1,5-dimethyl-1H-pyrazole-3-carboxylate (5.33 kg, 31 .7 mol) in THF (10.7 L) over 1.5 h at 4- 23 C, followed by THF (1.0 L). After 30 min, the solution was cooled to 15 C, then, while continuing to cool, a solution of water (0.66 L, 37 mol) in THF (1.9 L) was gradually added over 20 min. Aq. NaOH (15 wt%, 0.66 L, 2.8 mol) was then added over a few min, followed by water (2.0 L). The resulting slurry was stirred for 20 min at 4-1 1 C then filtered under suction. The collected solids were washed four times with THF (10.7 L per wash) to give (1 ,5-dimethyl-1 H- pyrazol-3-yl)methanol as a solution in the collected filtrates. (0239

The chemical industry reduces the impact on the environment during synthesis 5744-51-4. I believe this compound will play a more active role in future production and life.

83-10-3,Some common heterocyclic compound, 83-10-3, name is 1,5-Dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazole-4-carboxylic acid, molecular formula is C12H12N2O3, 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.

Step 1) N-(5-hydroxypyridin-2-yl)-L5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-lH- pyrazole-4-carboxamide [0191] To a suspension of 6-aminopyridin-3-ol (330 mg, 3 mmol) and 1,5- dimethyl-3-oxo-2-phenyl-2,3-dihydro-lH-pyrazole-4-carboxylic acid (710 mg, 306 mmol) in DMF (10 mL) was added EDCI (690 mg, 3.6 mmol) and HOAT (80 mg, 0.6 mmol). The reaction was stirred at 60 C for 4 hours, then cooled to rt and diluted with water (100 mL) and EtOAc (2 mL). The mixture was cooled to 0 C and stirred overnight. The resulted solid was collected through filtration to give title compound as a light brown solid (680 mg, 70 %). MS (ESI, pos. ion) m/z: 325.1 [M+H]+; NMR (400 MHz, DMSO-i): delta (ppm) 2.50 (s, 3H), 3.33 (s, 3H), 7.18-7.20 (dd, J= 2.3 Hz, 8.8 Hz, 1H), 7.40-7.42 (d, J= 7.5 Hz, 2H), 7.48-7.52 (m, 1H), 7.56-7.60 (m, 2H), 7.81-7.82 (d, J= 2.2 Hz, 1H), 7.95 (s, 1H), 8.04-8.06 (d, J= 8.8 Hz, 1H), 9.61 (s, 1H), 10.85 (s, 1H).

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 1,5-Dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazole-4-carboxylic acid, its application will become more common.

Some common heterocyclic compound, 5932-27-4, name is Ethyl 1H-pyrazole-3-carboxylate, molecular formula is C6H8N2O2, 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. 5932-27-4

1H-pyrazole-3-carboxylic acid ethyl ester (13.0g, 93 mmol) was dissolved in dimethylformamide (200ml). Potassium carbonate (32g, 232 mmol) was added to the solution, followed by 4-chloro-2- (bromomethyl) phenyl phenylmethyl ether (29g, 93 mmol) and the reaction mixture stirred overnight at room temperature under argon. Water and ethyl acetate were added and the layers separated. The aqueous phase was re-extracted with ethyl acetate. The organic phases were combined and washed with water followed by brine. The extracts were dried (Na2SO4) and evaporated. The residue was purified by on a biotage (15-25percent ethyl acetate: hexane) to yield the title compounds. 1- ( {5-chloro-2- [ (phenylmethyl) oxy] phenyl} methyl)-1H-pyrazole-3-carboxylic acid ethyl ester: (13. 90g, 40percent). t = 3.40, no ion observed.

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 5932-27-4, its application will become more common.

In the next few decades, the world population will flourish. As the population grows rapidly and people all over the world use more and more resources, all industries must consider their environmental impact. 139756-02-8, name is 4-Amino-1-methyl-3-N-propyl-1H-pyrazole-5-carboxamide belongs to pyrazoles-derivatives compound, it is a common compound, a new synthetic route is introduced below. 139756-02-8

General procedure: To a solution of 2-aminobenzamide (1.470 mmol, 1.0 eq.) was added to a solution of Terminal Alkyne (1.470 mmol, 1.0 eq.), Tosyl Azide, (1.470 mmol, 1.0eq.), CuI (0.147 mmol, 0.1 eq.), triethylamine (2.941 mmol, 2.0 eq.), in acetonitrile (10 ml) under N2 atmosphere. The mixture was stirred at room temperature for 12 h. After completion of the reaction (as indicated by TLC) the reaction mixture was poured into water (25 mL) and extracted with ethyl acetate (2×25 mL), dried over Na2SO4, concentrated under vacuum to get crude compound which was purified by column chromatography using a mixture of petroleum ether: ethyl acetate to give the desired product as a white solid.

The synthetic route of 139756-02-8 has been constantly updated, and we look forward to future research findings.

82560-12-1, In the next few decades, the world population will flourish. As the population grows rapidly and people all over the world use more and more resources, all industries must consider their environmental impact. 82560-12-1, name is 3-Amino-5-tert-butylpyrazole belongs to pyrazoles-derivatives compound, it is a common compound, a new synthetic route is introduced below.

A solution of [2-(6-bromo-pyridin-2-yloxy)-ethyl]-dimethyl-amine(WO2003/082278, 500 mg, 2.00 mmol), 3-tert-butyl-lH-pyrazole-5-amine (341 mg, 2.50 mmol) and trans-N,N’-dimethyl-cyclohexane-diamine (58.0 mg,0.40 mmol) was formed in toluene (5 mL). Potassium carbonate (592 mg, 4.30mmol) was added and the mixture degassed by bubbling N2 through it.Copper(I) iodide (39.0 mg, 0.20 mmol) was added and the mixture was sealedin a microwave vial and heated using microwave irradiation at 150C for 2 h.The resulting mixture was partitioned between EtOAc/Water and extractedwith EtOAc. The combined organics were dried over Na SO4, filtered andevaporated. Purification by FCC, eluting with a gradient of 0-10% [2M NH3/MeOH] in DCM, gave the crude title compound (428 mg, 69%) as a brown oil.

The synthetic route of 82560-12-1 has been constantly updated, and we look forward to future research findings.

175137-46-9, These common heterocyclic compound, 175137-46-9, name is 5-Cyclopropyl-1H-pyrazol-3-amine, 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.

The compound of example 33 (4.92 mmol) was reacted with 5-cyclopropyl-1H-pyrazol-3-amine(5.91 mmol) in presence of DMF (4.92 mmol), ethanol (148 mmol), sodium iodide (4.92 mmol)and triethylamine (24.62 mmol). The reaction mixture was stirred at a temperature of 100 C for 2 days. The DMF and excess triethylamine was evaporated followed by addition of water and ethyl acetate. The organic layer was separated and concentrated for purification using column chromatography (silica gel, 0.5 % methanol dichloromethane) to obtain the title compound.Yield: 70.1 %; ?H NMR (DMSO-d6, 300 MHz): oe 12.14 (s, 1H), 9.00 (s, 1H), 6.23(s, 1H), 2.59 (bs, 2H), 2.50 (d, 1=9.9Hz, 2H), 1.90 (m, 1H), 1.73 (bs, 4H), 0.93 (d, 1=6.6Hz, 2H), 0.69 (m, 2H); MS (ES+): mlz 418.3 (M+1).

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 175137-46-9.

26621-44-3, Name is 3-Nitro-1H-pyrazole, 26621-44-3, belongs to pyrazoles-derivatives compound, is considered to be a conventional heterocyclic compound, which is widely used in drug synthesis. The chemical synthesis route is as follows.

Into a 250-mL round-bottom flask was placed a solution of 3-nitro-lH-pyrazole (10 g, 88.4 mmol) in DMF (100 mL). This was followed by the addition of NaH (60% wt, 3.9 g, 97.5 mmol) in portions at 0C. The resulting solution was stirred for 0.5 h at 0C. This was followed by the addition of 2-bromopropane (14.1 g, 114.6 mmol) dropwise with stirring at 0C in 10 min. The resulting solution was stirred for 16 h at RT and then was quenched by the addition of 100 mL of water. The resulting solution was extracted with 3×100 mL of ethyl acetate. The organic layers were combined and dried over anhydrous Na2S04, then concentrated under vacuum. The residue was applied onto a silica gel column and eluted with a gradient of ethyl acetate/petroleum ether (1 :5 to 1 :3). This resulted in 11.8 g (86%) of the title compound as yellow oil. MS-ESI: 156.1 (M+l).

Statistics shows that 3-Nitro-1H-pyrazole is playing an increasingly important role. we look forward to future research findings about 26621-44-3.

A common heterocyclic compound, 3469-69-0, name is 4-Iodopyrazole, molecular formula is C3H3IN2, 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. 3469-69-0.

To a solution of 4-iodo-1H-pyrazole (2.0 g, 10.31 mmol) in tetrahydrofuran (20 mL) was added sodium hydride (619 mg, 15.47 mmol) at 0 C. The resulting white suspension was stirred at 0 C for 2 hours. 2-(chloromethoxyethyl)trimethyl silane (SEM-Cl, 90% purity, 2.101 g, 2.230 mL, 11.34 mmol) was added dropwise at 0 C. The suspension was then allowed to warm up to room temperature and stirred for 16 hours. The reaction was quenched with water (0.5 mL), and concentrated to ~5 mL at reduced pressure. The mixture was then partitioned between EtOAc (50 mL) and saturated NaHCC solution (30 mL). The organic layer was separated, washed with brine (20 ml_), dried (Na2S04) and concentrated at reduced pressure. The residue was purified by Biotage Isolera chromatography [SNAP Cartridge KP-Sil 50 g; eluting with a gradient of eluents; 0-20% EtOAc in heptane] to give the title compound (3.27 g, 91% yield) as a colourless oil. 1H NMR (500 MHz, chloroform-d) delta [ppm] 7.62 (s, 1 H), 7.54 (s, 1 H), 5.40 (s, 2H), 3.59 – 3.51 (m, 2H), 0.94 – 0.85 (m, 2H), -0.02 (s, 9H). LCMS (Analytical Method A): Rt = 1.36 mins; MS (ESIPos) m/z = 324.9 (M+H)

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

Adding some certain compound to certain chemical reactions, such as: 82560-12-1, name is 3-Amino-5-tert-butylpyrazole, 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 82560-12-1. 82560-12-1

To a solution of methyl-4-iodo-2-methoxybenzoate (10.0 g, 34.2 mmol) in toluene (90 mL) was added 3-fe/f-butyl-1 H-pyrazol-5-amine (5.24 g, 37.7 mmol) followed by (1 R,2R)-/V1,/V2- dimethylcyclohexane-1 ,2-diamine (870 mg, 1 .08 mL, 6.85 mmol) and potassium carbonate (14.9 g, 108 mmol). The mixture was purged with N2, copper(l) iodide (326 mg, 1 .71 mmol) was added and the reaction mixture was heated at reflux under N2 for 18 hr. The mixture was cooled to RT and was partitioned between EtOAc (100 mL) and water (3 x 150 mL). The organic layer was separated and washed with aq. citric acid solution (1 % w/v, 150 mL) followed by water (150 mL), and was then dried and evaporated in vacuo. The residue was purified by flash column chromatography (Si02, 330 g, EtOAc in isohexane, 0-100%, gradient elution) to afford methyl 4-(5-amino-3-ie f-butyl-1 /-/-pyrazol-1 -yl)-2-methoxybenzoate as a buff coloured solid (3.62 g, 35%); Rl 1.93 min (Method 2); m/z 304 (M+H)+ (ES+).

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 3-Amino-5-tert-butylpyrazole.

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. 14521-80-3, name is 3-Bromo-1H-pyrazole, A new synthetic method of this compound is introduced below., 14521-80-3

Step C: Preparation of2-(3-Bromo-1 H-pyrazol- 1 -yl)-3-chloropyridineTo a mixture of 2,3-dichloropyridine (27.4 g, 185 mmol) and 3-bromopyrazole (i.e. the product of Step B) (25.4 g, 176 mmol) in dry N,N-dimethylformamide (88 mE) was added potassium carbonate (48.6 g, 352 mmol), and the reaction mixture was heated to 125 C. for 18 hours. The reaction mixture was cooled to room temperature and poured into ice water (800 mE). A precipitate formed. The precipitated solids were stirred for 1.5 hrs, filtered and washed with water(2×100 mE). The solid filter cake was taken up in methylene chloride and washed sequentially with water, iN hydrochlonc acid, saturated aqueous sodium bicarbonate solution, and brine. The organic extracts were then dried over magnesium sulfate and concentrated to afford 39.9 g of a pink solid. Thecrude solid was suspended in hexane and stirred vigorously for 1 hr. The solids were filtered, washed with hexane and dried to afford the title product as an off-white powder (30.4 g) determined to be >94% pure by NMR. This material was used without thrther purification in Step D.?H NMR (CDC13) oe 6.52 (s, 1H), 7.30 (dd, 1H), 7.92 (d, 1H), 8.05 (s, 1H), 8.43 (d, 1H).

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.