pyrazoles-derivatives

Some common heterocyclic compound, 31728-75-3, name is 1,5-Dimethyl-1H-pyrazole-4-carboxylic acid, 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. Quality Control of 1,5-Dimethyl-1H-pyrazole-4-carboxylic acid

The 4-amino-l,5-dimethyl-lH-pyrazole used as a starting material was prepared as follows :-Under an atmosphere of argon, diisopropylethylamine (3.49 ml) and diphenylphosphoryl azide (2.37 ml) were added in turn to a stirred mixture of 1 ,5-dimethyl-l/J-pyrazole-4-carboxylic acid (1.4 g), fer/-butanol (4 ml) and 1,4-dioxane (40 ml) and the reaction mixture was stirred at ambient temperature for 10 minutes. The resultant mixture was heated to 110C for 3 hours. The solvent was evaporated and the reaction product was purified by column chromatography on silica using ethyl acetate as the eluent. There was thus obtained 4-(fert-butoxycarbonylamino)- 1,5 -dimethyl- lH-pyrazole (0.225 g); 1H NMR: (DMSOd6) 1.4 (s, 9H), 2.2 (s, 3H), 3.55 (s, IH), 6.0 (br s, IH), 9.3 (br s, IH).

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 31728-75-3, its application will become more common.

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. 152120-54-2, name is tert-Butyl (((tert-butoxycarbonyl)amino)(1H-pyrazol-1-yl)methylene)carbamate, A new synthetic method of this compound is introduced below., Safety of tert-Butyl (((tert-butoxycarbonyl)amino)(1H-pyrazol-1-yl)methylene)carbamate

To a solution of compound 14 (40 mg, 1 eq) in 2 ml anhydrous DCM, TEA (40 muIota, 4 eq) was added. The solution was cooled down to 0 C and N, N’-Di-Boc-1 H-pyrazole-1-carboxamidine (42 mg, 2 eq) added. The reaction mixture was allowed to warm up to room temperature and kept stirring overnight. After completion, the reaction was quenched with water, extracted with ethyl acetate. The organic phase was washed with brine, dried over Na2S04, concentrated and purified by flash chromatography to give the desired product. Crude product, 40 mg (72%).1H NMR (500 MHz, CD3OD) delta 8.55 (s, 1 H, Triazole-H5), 8.06 (d, J = 8.3 Hz, 2H, Ar-H), 7.92 (d, J = 8.3 Hz, 2H), 6.00 (d, J = 2.3 Hz, 1 H, H-3), 5.58 (d, J = 1.5 Hz, 1 H, H-7), 5.56 – 5.52 (m, 1 H, H-8), 5.31 (dd, J = 14.8, 2.4 Hz, 1 H, H-9), 5.02 (dd, J = 10.2, 2.3 Hz, 1 H, H-4), 4.74 (dd, J = 14.8, 9.0 Hz, 1 H, H-9′), 4.53 (dd, J = 10.2, 1.5 Hz, 1 H, H-6), 4.27 (t, J = 10.2 Hz, 1 H, H-5), 3.91 , 3.80 (2 x s, 3H, COOCH3), 2.12, 1 .94, 1.85 (3 x s, 3 x 3H, 3 x COCH3), 1 .51 , 1 .46 (2 x s, 2 x 9H, 2 x Boc).13C NMR (125 MHz, CD3OD) delta 173.57, 171 .77, 171.41 , 168.07, 164.32, 163.39, 158.01 (C=0), 153.82 (C=N), 147.64 (Triazole-C4), 124.50 (Triazole-C5), 145.61 (C-2), 136.34, 131.27, 131.27, 126.55 (Ar-C), 11 1.83 (C-3), 84.84, 80.57 (>Boc-C(CH3)3), 78.89 (C-6), 74.00 (C-8), 69.87 (C-7), 53.07, 52.74 (COOCH3), 51.27 (C-9), 50.84 (C- 4), 47.90 (C-5), 28.59, 28.26 (‘Betaomicronomicron-0(OmicronEta3)3), 22.77, 20.86, 20.65 (COCH3). HR-MS (ESI) calcd. for C37H49N7NaOi4 [M+Na]+, 838.3235; found 838.3226.

The synthetic route of 152120-54-2 has been constantly updated, and we look forward to future research findings.

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. 127107-23-7, name is 1-Methyl-1H-pyrazol-4-amine hydrochloride, This compound has unique chemical properties. The synthetic route is as follows., Quality Control of 1-Methyl-1H-pyrazol-4-amine hydrochloride

To a solution of tert-butyl ((1S,5R,6R)-3-(2-chloro-5-fluoropyrimidin-4-yl)-6-methyl-3-azabicyclo[3.1.0]hexan-1-yl)carbamate (42, 1.0 g, 2.91 mmol) in isopropanol (10 mL) was added 1-methyl-1H-pyrazol-4ylamine hydrochloride (506 mg, 3.79 mmol) and the reaction was heated to 140 C under microwave irradiation for 1 h. The resulting solid was filtered and dried to afford (1S,5R,6R)-3-(5-fluoro-2-((1-methyl-1H-pyrazol-4-yl)amino)pyrimidin-4-yl)-6-methyl-3-azabicyclo[3.1.0]hexan-1-amine hydrochloride (43, 991 mg, 86%). MS m/z 304 [M+H]+

According to the analysis of related databases, 127107-23-7, the application of this compound in the production field has become more and more popular.

Reference of 1752-88-1, These common heterocyclic compound, 1752-88-1, name is 3-Pyrazolidinone hydrochloride, 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.

Alkylation of 20 with 21 to give 22 Potassium carbonate (8.28 g, 60.0 mmol), methyl 5-(3-bromopropyl)-thiophene-2-carboxylate (21, for preparation, see Billot, X. et al WO2004/037786, incorporated by reference herein, 5.66 g, 21.5 mmol), 3-pyrazolidinone HCl (20, 2.57 g, 21.0 mmol) and DMF (25 mL) were combined under argon and stirred at rt. After 3 d at rt, HPLC analysis indicated the reaction to be complete and EtOAc (100 mL) was added. The mixture was washed with water (2¡Á75 mL). The combined aqueous phase was back-extracted with EtOAc (50 mL). The combined organic phase was washed with brine (75 mL), filtered through filter paper and concentrated in vacuo to afford 7.5 g of a crude oil. Purification of the crude product by flash column chromatography on 75 g silica gel (50% CH2Cl2/hexane?CH2Cl2?20% EtOAc/CH2Cl2?100% EtOAc?10% MeOH/EtOAc, gradient) afforded 3.2 g (57%) of 22 which solidified on standing.

The synthetic route of 1752-88-1 has been constantly updated, and we look forward to future research findings.

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. 2458-26-6, name is 3-Phenyl-1H-pyrazole, A new synthetic method of this compound is introduced below., HPLC of Formula: C9H8N2

1.57 g of 3-phenylpyrazole was dissolved in 11 ml of N,N-dimethylformamide. To the resulting solution was added 0.50 g of 60% sodium hydride, and the entire mixture was stirred for 1.5 hours at room temperature. To this mixture was added a solution containing 2.90 g of the 1-tert-butoxycarbonylpiperidin-4-yl methanesulfonate dissolved in 2 ml of N,N-dimethylformamide, and the entire mixture was stirred for two hours at 50C, one hour at 70C, and then 3.5 hours at 100C. The reaction liquid was then poured into water, and extracted twice with ether. The organic layer was washed three times with water and dried over anhydrous magnesium sulfate, and the solvent was then removed by evaporation under reduced pressure. The residue was purified by silica gel column chromatography (developing solvent: hexane/ethyl acetate = 4/1 (volume ratio)), yielding 1.54 g of the target compound.

The synthetic route of 2458-26-6 has been constantly updated, and we look forward to future research findings.

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. 27258-33-9, name is 1-Methyl-1H-pyrazole-5-carbaldehyde, This compound has unique chemical properties. The synthetic route is as follows., SDS of cas: 27258-33-9

(ii) (1-Methyl-1 H-pyrazol-5-yl)methanol was prepared as follows (c.f. Bioorg. Med. Chem., 2001 , 9, 961-982): A stirred solution of 1-methyl-1 H-pyrazole-5- carbaldehyde (5.2 g, 47 mmol) in ethanol (50 ml) at 5C was treated with sodium borohydride (893 mg, 23. 5mmol). The reaction mixture was stirred at 5C for 30 minutes, hydrochloric acid (5N, 10 ml) was added and the organic solvent was evaporated. The residue was partitioned between ethyl acetate and water. The layers were separated and the aqueous solution was saturated with sodium chloride and re-extracted with ethyl acetate. The combined organic extracts were washed with brine, then dried and evaporated to afford (1-methyl-1 H-pyrazol-5-yl)methanol which was used in the next step.

According to the analysis of related databases, 27258-33-9, the application of this compound in the production field has become more and more popular.

Electric Literature of 285984-25-0,Some common heterocyclic compound, 285984-25-0, name is 3-(tert-Butyl)-1-(p-tolyl)-1H-pyrazol-5-amine, molecular formula is C14H19N3, 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.

In a 250 mL round botom flask, 100 mL of ethanol was added, (30 mmol) of pivaloylacetonitrile, (33.63 mmol) of 4-methylphenylhydrazine, A solution of 3.6 mL of concentrated hydrochloric acid was added dropwise with stirring,Heated to reflux for 8 hours, cool down, concentrate, The residue was adjusted to pH 10-11 with dilute sodium hydroxide, Extracted three times with ethyl acetate, Dried over anhydrous sodium sulfate, concentrate, The resulting solid was recrystallized from ethyl acetate / petroleum ether to give white crystals C, Yield 80.3%. 5-tert-butyl-2-p-methylphenyl-3-aminopyrazole (3.5 mmolC) was placed in a 100 ml three-Dissolved in 30 ml of tetrahydrofuran, Place the three-necked flask in a cryogenic tank to cool to -20 C, 2.9 g of sodium bicarbonate was added in portions with stirring, After 15 min, A solution of trichloroethyl chloroformate (3.5 mmol) was added dropwise, Control the solution temperature does not exceed 0 deg C, After dripping, Continue stirring for 30min, And then heated to 0 C for 12 h. After completion of the reaction, The mixture is filtered, The residue was washed with ethyl acetate, The filtrate was concentrated, Yield 85%.

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 3-(tert-Butyl)-1-(p-tolyl)-1H-pyrazol-5-amine, its application will become more common.

Synthetic Route of 67-51-6, 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. 67-51-6 name is 3,5-Dimethyl-1H-pyrazole, 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.

General procedure: 1-benzyl-4-chloro-3,5-dimethyl-1H-pyrazole. To a 16 mL vial containing 1-benzyl-3,5-dimethyl-1H-pyrazole (196 mg, 1.05 mmol) and a magnetic stir bar, 0.7 mL of water and 0.3 mL of ethyl acetate was added. Next, NaCl (123 mg, 2 mmol) was added and the vial was placed in a room temperature water bath to control exotherms. Finally, Oxone (322 mg, 0.52 mmol or 1.05 mmol KHSO5) was added and the vial was capped. The reaction proceeded with continuous and vigorous stirring until no starting material remained as indicated by TLC (1 h). The remaining oxidants were reduced with solid sodium bisulfite until starch iodide paper tested negative. Water (5 mL) was added and the mixture was extracted with 1:1 hexanes/diethyl ether (3 x 5 mL). The combined organic fractions were dried (MgSO4) and concentrated to yield crude product that was purified by flash chromatography (14 x 1 cm), 9:1 hexane/ethyl acetate eluent. Pure 1-benzyl-4-chloro-3,5-dimethyl-1H-pyrazole was obtained as a pale yellow oil (215 mg, 93% yield).

At the same time, in my other blogs, there are other synthetic methods of this type of compound, 3,5-Dimethyl-1H-pyrazole, and friends who are interested can also refer to it.

Reference of 1260243-04-6, A common heterocyclic compound, 1260243-04-6, name is Ethyl 5-amino-1H-pyrazole-4-carboxylate, molecular formula is C6H9N3O2, 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 solution of ethyl 5-amino-lH-pyrazole-4-carboxylate (3.0 g, 19.3 mmol) in acetic acid (40 mL) and ethanol (10 mL) was added 1,1,3,3-tetramethoxypropane (3.48 g, 21.4 mmol). The reaction mixture was stirred at 90 ¡ãC overnight and cooled down to room temperature and then concentrated in vacuo. The residue was diluted with ethyl acetate (100 mL) and washed with saturated NaHC03aqueous solution (20 mL) and then dried over anhydrous Na2S04, filtered and concentrated in vacuo. The residue was purified by a silica gel column chromatography (DCM/EA (v/v) = 6/1) to give the title compound as a light yellow solid (3.2 g, 85percent).LC-MS (ESI, pos. ion) m/z: 192.3 [M+H]+; H NMR (600 MHz, CDC1 ): delta (ppm) 8.81 (m, 1H), 8.78 (m, 1H), 8.61 (s, 1H), 7.04 (dd, J = 6.9, 4.1 Hz, 1H), 4.47 (q, J= 7.1 Hz, 2H), 1.44 (t, J = 7.1 Hz, 3H).

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.

Electric Literature of 313735-62-5, 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. 313735-62-5 name is 4-Bromo-1-isopropylpyrazole, 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.

4-bromo-1-(isopropyl)-1H-pyrazole 11d (200 mg, 1.06 mmol) was dissolved in dry THF (6 mL) at -78 Cunder nitrogen and was stirred for 10 min. n-BuLi (2.5 M in hexanes, 0.44 mL, 1.11 mmol) was added drop wise to the solution was stirred for 2 h at -78 C. After two hours, ethyl difluoroacetate (0.11 mL, 1.27 mmol) was added drop wise and stirred for 10 min at -78 C uponwhich the mixture was then quenched with NH4Cl (20 mL) and warmed to room temp. Themixture was then extracted with ether (50 mL), and dried over MgSO4. After concentration invacuo (note: remove shortly after the ether is removed, because the compound is quite volatile),the residue was purified with flash chromatography over silica gel (hexane: ethyl acetate =80:20) to yield the product as a clear oil in 48% yield (0.1 g).

At the same time, in my other blogs, there are other synthetic methods of this type of compound, 4-Bromo-1-isopropylpyrazole, and friends who are interested can also refer to it.