Tag: M.W:200-300

Synthetic Route of 2033-45-6, 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. 2033-45-6 name is 3,5-Dimethyl-4-iodopyrazole, 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.

(b) 4-iodo–3,5-dimethyl- I -tosyl- 1 H-pyrazole: Triethylamine (1 2.73g, 126. 8nunol) was added toa solution of 4-iodo-3,5-dimeihyl-1H-pyrazole (141)7g. 63.4nimol) in DCM (250 mL), followed byaddition of TsC1 (13.3g 69,7minoi). The mixture was then stirred overnight. After completionof the reaction, water (100 mL) was added and the mixture was extracted with EtOAc (3x80m1). The orgamie solvent was collected and removed under reduced pressure, the residue was purified by silica gel-column to obtaine 4-iodo-3,5-dhnethyl-1-tosyl-IH-pyrazoie (8.0g. yield 33.6%) as a white solid ,LCMS (022): 222.7 [M+H]t Rt :1.65 mm

At the same time, in my other blogs, there are other synthetic methods of this type of compound, 3,5-Dimethyl-4-iodopyrazole, and friends who are interested can also refer to it.

These common heterocyclic compound, 1145-01-3, name is 3,5-Diphenyl-1H-pyrazole, 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. COA of Formula: C15H12N2

To a flame dried flask was added 3,5-diphenylpyrazole (0.21 g, 0.95 mmol), Selectfluor (0.76 g, 2.1 mmol), and dried, ground molecular sieves (3 A) (0.5 g) followed by dry acetonitrile (distilled from CaH2 and stored over molecular sieves) (3 mL) and the mixture was heated at 80 C (oil bath temp) under N2 for 40 min. The dark yellow solution was then diluted with EtOAc and filtered. The filtrate was evaporated onto silica gel and subjected to flash chromatography on silica gel using 10:1 hexanes/EtOAc as eluent to give first difluoropyrazole 2 (0.19 g, 74% yield) and then the hydrated difluoropyrazole 3 (0.054 g, 20% yield) as yellow solids. The products were recrystallized from hexanes (2) or cyclohexane (3) to give analytical samples as pale yellow crystals. Data for 4,4-difluoro-3,5-diphenyl-4H-pyrazole (2): mp 91.2-91.8 C. IR (ATR): 3071, 3054, 1594, 1582, 1556, 1497, 1447, 1379, 1353, 1339, 1220, 1101, 1021, 872, 777, 720, 698, 681 cm-1. 1H NMR (300 MHz, DMSO-d6): 8.05 (d, J = 7.5 Hz, 4H), 7.74-7.64 (m, 6H). 13C NMR (75 MHz, DMSO-d6): 161.8 (t, J = 22.7 Hz), 133.8 (s), 129.9 (s), 127.8 (s), 125.7 (t, J = 265.9 Hz), 124.7 (s). 19F NMR (282 MHz, DMSO-d6): -116.4 (s). Anal. calcd for C15H10F2N2: C, 70.30; H, 3.93; N, 10.93; found: C, 70.41; H, 4.02; N, 10.82. Data for 4,4-difluoro-3,5-diphenyl-4,5-dihydro-1H-pyrazol-5-ol (3): mp 105.6-106.3 C. IR (ATR): 3354, 3238 (broad), 1593, 1571, 1491, 1332, 1449, 1238, 1136, 1068, 1050, 1016, 964, 889, 778, 688, 656, 635 cm-1. 1H NMR (300 MHz, DMSO-d6): 8.77 (s, 1H), 7.69 (d, J = 7.2 Hz, 2H), 7.59-7.56 (m, 2H), 7.48-7.40 (m, 6H), 7.31 (s, 1H). 13C NMR (75 MHz, acetone-d6): 143.9 (dd, J = 22.5 Hz, 24.0 Hz), 136.8 (d, J = 2.3 Hz), 134.2 (s), 130.1 (s), 129.8 (s), 129.6 (s), 128.9 (s), 128.2 (d, J = 1.6 Hz), 126.2 (d, J = 1.6 Hz), 125.3 (dd, J = 251.7 Hz, 261.9 Hz), 92.9 (dd, J = 20.8 Hz, 32.4 Hz). 19F NMR (282 MHz, DMSO-d6): -103.4 (d, J = 259 Hz), -122.7 (d, J = 259 Hz). Anal. calcd for C15H12F2N2O: C, 65.68; H, 4.41; N, 10.21; found: C, 65.58; H, 4.39; N, 10.23.

The synthetic route of 3,5-Diphenyl-1H-pyrazole has been constantly updated, and we look forward to future research findings.

Synthetic Route of 39806-90-1, A common heterocyclic compound, 39806-90-1, name is 4-Iodo-1-methyl-1H-pyrazole, molecular formula is C4H5IN2, 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.

Step 1 1-Methyl-4-(methylthio)-1H-pyrazole To a solution of 4-iodo-1-methyl-1H-pyrazole (0.5 mL, 5.2 mmol) in THF (2 mL) at -78 C. under an atmosphere of N2 was added isopropylmagnesium chloride (5.2 mL, 10.4 mmol) and the resulting mixture was stirred for 30 minutes. To the reaction mixture was added dimethyl disulfide (1 mL, 11 mmol). The reaction was poured into aq. sat. NH4Cl (25 mL), the layers were separated and the aqueous layer was extracted with Et2O (100 mL). The combined organic layers were dried over Na2SO4, filtered, and concentrated under reduced pressure. The residue was purified by reverse phase preparative HPLC (Mobile Phase: A=10 mM NH4HCO3 in H2O, B=MeCN; Gradient: B=95%; 13 min; 30 mL/min; column: Xtimate Prep C18 OBD 21.2*250 mm, 10 mum) to afford the title compound (740 mg, 29%) as an off-white solid. (ES+) C5H8N2S requires: 128, found: 129 [M+H]+.

The synthetic route of 39806-90-1 has been constantly updated, and we look forward to future research findings.

Application of 1280210-79-8, The chemical industry reduces the impact on the environment during synthesis 1280210-79-8, name is tert-Butyl 4,6-dihydropyrrolo[3,4-c]pyrazole-5(2H)-carboxylate, I believe this compound will play a more active role in future production and life.

INTERMEDIATE 6; 2-(2-Hydroxy-2-methylpropyl -2,4,5,6-tetrahydropyrrolo[3,4-c]pyrazol-5-ium trifluoroacetate saltTo a stirred solution of tert-butyl 2,6-dihydropyrrolo[3 ,4-c]pyrazole-5(4H)-carboxyIate(35 g, 167 mmol) in DMF (500 mL) at 0 C under N2 was added sodium hexamethyldisilazide in THF (351 mL, 351 mmol) and the mixture was stirred at 0 C for 30 min. Isobutylene oxide (74.3 mL, 836 mmol) was then slowly added. The solution was stirred at 0C for 0.5 h and then stirred at room temperature for 1 h. The solution was heated to 80C for 100 min in a microwave oven, cooled to room temperature and evapoarted under vacuum. The residue was purified by column chromatography on silica gel, eluting with a gradient of 0% to 6% CH2Cl2 MeOH (containing 1 % NH4OH) to give a mixture of two regioisomers. The mixture of tworegioisomers A and B was resolved by chromatography on a ChiralPak AD-H column eluting with 4-40% MeOH/C02 to give isomer A as the faster eluting isomer and isomer B as the slower eluting isomer. NMR (500 MHz, CD3OD) for isomer B: 67.42 (d, 1 H); 4.42 (s, 2H); 4. 1 (s, 2H); 4.07 (s, 2H); 1.51 (d, 9H); 1.16 (s, 6H). LC-MS: 226.27 (M+l-56).The desired isomer B was treated with 1 :1 TFA/C?C12 for 1 h to give the title compound. NMR (500 MHz, CD3OD): 57.55 (s, 1H); 4.43 (s, 2H); 4.39 (s, 2H); 4.10 (s, 2H);1.17 (s, 6H). LC-MS: 182.31 (M+l).

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, tert-Butyl 4,6-dihydropyrrolo[3,4-c]pyrazole-5(2H)-carboxylate, other downstream synthetic routes, hurry up and to see.

Application of 6076-14-8, These common heterocyclic compound, 6076-14-8, name is Ethyl 4-bromo-5-methyl-1H-pyrazole-3-carboxylate, 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.

ethyl 4-bromo-5-methyl-1 H-pyrazole-3-carboxylate (p76, 900 mg, 3.86 mmol) was dissolved in DMF (6 mL) and cooled with an ice bath. Then NaH 60% dispersion in oil (309 mg, 7.72 mmol) was added portion-wise and the resulting mixture was stirred for 30 min before adding iodomethane (0.29 mL, 4.63 mmol). The reaction mixture was stirred at RT for 3 hrs. It was diluted with water and extracted with EtOAc (3x). The organic phase was dried and evaporated and the residue was purified by S1O2 column (eluting from cHex to 50% EtOAc) to afford ethyl 4-bromo-2,5-dimethyl-1 H-pyrazole-3- carboxylate (260 mg) as oil and ethyl 4-bromo-1 ,5-dimethyl-1 H-pyrazole-3-carboxylate (p77, y= 44% yield) as white solid. NMR (1H, DMSO-c/6) delta 4.26 (q, 2H), 3.86 (s, 3H), 2.27 (s, 3H), 1.28 (t, 3H)

Statistics shows that Ethyl 4-bromo-5-methyl-1H-pyrazole-3-carboxylate is playing an increasingly important role. we look forward to future research findings about 6076-14-8.

Related Products of 5334-28-1,Some common heterocyclic compound, 5334-28-1, name is 5-Amino-1-(4-bromophenyl)-1H-pyrazole-4-carbonitrile, molecular formula is C10H7BrN4, 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: A suspension of the appropriate derivatives 2a-d or 9(0.001 mol) was dissolved in glacial acetic acid (3 mL) then POCl3(0.2 mL) was added quickly. The reaction mixture was refluxedfor 2 h (the reaction system was carefully observed by TLC). Aftercooling the mixture, ice-water was added and the formed precipitatewas filtered, washed with water, dried and recrystallized fromformic acid to give compounds 3e-h or 10b

The synthetic route of 5334-28-1 has been constantly updated, and we look forward to future research findings.

37687-24-4, name is Diethyl 3,5-pyrazoledicarboxylate, 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. SDS of cas: 37687-24-4

A mixture of 2-bromo-1-(4-methyl-3,4-dihydro-2H-1,4-benzoxazin-6-yl)ethanone hydrobromide (Intermediate 28A, 1.77 g, 3.2 mmol, 63% purity), diethyl 1H-pyrazole-3,5-dicarboxylate (642 mg, 3.0 mmol) and potassium carbonate (2.09 g, 15.1 mmol) in acetone (40 ml) was stirred overnight at room temperature. The solids were filtered off, and the filtrate was concentrated under re- duced pressure. The residue was purified by flash-chromatography on silica gel (eluent: petrole- um ether/ ethyl acetate 2:1) to give 1.18 g (96% of theory) of the title compound. LC/MS [Method 14]: Rt = 1.21 min; MS (ESIpos): m/z = 402 [M+H]+. 1H-NMR (300 MHz, DMSO-d6): d [ppm] = 7.44 (s, 1H), 7.28-7.33 (m, 2H), 6.83 (d, 1H), 6.06 (s, 2H), 4.36-4.45 (m, 4H), 4.28 (q, 2H), 3.28-3.31 (m, 2H), 2.92 (s, 3H), 1.40 (t, 3H), 1.31 (t, 3H).

The synthetic route of 37687-24-4 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. 39806-90-1, name is 4-Iodo-1-methyl-1H-pyrazole, A new synthetic method of this compound is introduced below., HPLC of Formula: C4H5IN2

Reference Example 140 tert-butyl ({4-(2-fluorophenyl)-5-[(1-methyl-1H-pyrazol-4-yl)thio]-1,3-thiazol-2-yl}methyl)methylcarbamate To a solution of 2-ethylhexyl 3-{[2-{[(tert-butoxycarbonyl)(methyl)amino]methyl}-4-(2-fluorophenyl)-1,3-thiazol-5-yl]thio}propanoate (356 mg) in ethanol (4 mL) was added sodium ethoxide (89 mg) at 0 C., and the mixture was stirred at room temperature for 1 hr, and concentrated under reduced pressure. A mixture of the residue, 4-iodo-1-methyl-1H-pyrazole (155 mg), tris(dibenzylideneacetone)dipalladium(0) (32 mg) and 9,9-dimethyl-4,5-bis(diphenylphosphino)xanthine (39 mg) was stirred in toluene (5 mL) at 80 C. for 2 hr. The reaction mixture was allowed to cool to room temperature, water was added, and the mixture was extracted with ethyl acetate. The extract was washed successively with saturated aqueous sodium hydrogen carbonate solution, water and saturated brine, dried over anhydrous sodium sulfate, and concentrated under reduced pressure. The residue was purified by basic silica gel column chromatography (eluent: hexane-ethyl acetate=1:1) to give the title compound as a yellow oil (208 mg, yield 27%). 1H-NMR (CDCl3) delta: 1.46 (9H, brs), 2.94 (3H, brs), 3.85 (3H, s), 4.58-4.62 (2H, m), 7.15-7.26 (2H, m), 7.37-7.44 (3H, m), 7.48-7.53 (1H, m).

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.

Related Products of 13599-12-7, These common heterocyclic compound, 13599-12-7, name is Ethyl 3-phenyl-1H-pyrazole-5-carboxylate, 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.

Ethyl 2,4-dioxo-4-phenylbutanoate (16b) (2.6 g, 9.1 mmol)Dissolved in 30mL of methanol, added 15mL lithium hydroxide monohydrate(0.5 g, 20.0 mmol) in water. The reaction was heated to 70 C until the hydrolysis was complete. Concentration under reduced pressure gave a solid suspension. 15 mL of water was added and the pH was adjusted to 3 with 1 N diluted hydrochloric acid. Filtering,The title compound 5-phenyl-1H-pyrazole-3-carboxylic acid (Intermediate 16) was obtained.Dark white solid (2.1 g, yield 89.5%).

Statistics shows that Ethyl 3-phenyl-1H-pyrazole-5-carboxylate is playing an increasingly important role. we look forward to future research findings about 13599-12-7.

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. 155377-19-8, name is Ethyl 3-(trifluoromethyl)pyrazole-4-carboxylate, A new synthetic method of this compound is introduced below., Formula: C7H7F3N2O2

According to the procedure of Buchwald et al . (J. Oxg. Chem. 2004, 69, 5578), to a 350 iaL sealed tube flushed vigorously with nitrogen was added ethyl 3- (trifluoromethyl) – lH-pyrazole-4-carboxylate (20.0 g, 96.1 mmol) , 1-iodobenzene (12.9 inL, 115 mmol), potassium carbonate (27.9 g, 202 mmol), copper(I) iodide (0.915 g, 4.80 mmol), and (IS, 2S) -N1,N2- dimethylcyclohexane-l,2-diamine (1.37 g, 9.61 mmol), followed by degassed (argon) toluene (100 mL) . The mixture was stirred for 24 hours at 1100C, cooled to room temperature, and filtered through a short silica pad which was thoroughly rinsed with toluene and AcOEt- The filtrate was concentrated in vacuo to give ethyl l-phenyl-3- (trifluoromethyl) -lH-pyrazole-4- carboxylate (21 g, 77%) as a solid: 1H NMR (400 MHz, CDCl3) delta 1.39 (t, 3H, J = 7.0 Hz), 4.37 (q, 2H, J = 7.0 Hz), 7.42 (m, IH), 7.52 (m, 2H), 7.72 (m, 2H), 8.48 (m, IH).

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.