Month: August 2020

15456-86-7, 4-Bromo-1,2-dihydropyridazine-3,6-dione is a pyridazine compound, ?involved in a variety of chemical synthesis. Rlated chemical reaction is continuously updated

Preparation A; 6,7-Dihydro [1 ,4] dioxino [2,3-c] pyridazine-3-carbaldehyde; (a) 3,4,6-Trichloropyridazine; This was prepared by a slight variation on the method of Kasnar et al,Nucleosides & Nucleotides (1994), 13(1-3), 459-79.Hydrazine sulphate salt (51 g) was suspended in water (250ml), heated to reflux and bromomaleic anhydride (90.38 g) was added dropwise . The mixture was heated at reflux for 4 hours then cooled to room temperature. The reaction was repeated with 29g hydrazine sulphate, 53 g bromomaleic anhydride and 130ml water. The precipitates were collected by filtration, washed with water and acetone and dried as a combined batch in vacuo to afford 4-bromo-l,2-dihydro-3,6-pyridazinedione as a white solid (113 g).The solid in two batches was treated with phosphorus oxychloride (2×200 ml) and heated to reflux for 3.5 hours. The mixture was cooled, evaporated and azeotroped with toluene. The residue was partitioned between dichloromethane and saturated aqueous sodium bicarbonate solution and extracted with DCM twice more. The organic extracts were dried and evaporated. This residue was re-dissolved in dichloromethane, and chromatographed on silica gel (300 g) (DCM as eluent) to give a white solid (101.5 g, 87%). (LC/MS analysis showed ca 20-30% impurity, isomers of bromo-dichloropyridazine). MS (+ve ion electrospray) m/z 184/185/186 (MH+), trichloropyridazine. MS (+ve ion electrospray) m/z 228/229/231 (MH+), bromo-dichloropyridazine.

As the paragraph descriping shows that 15456-86-7 is playing an increasingly important role.

Reference£º
Patent; GLAXO GROUP LIMITED; WO2008/128942; (2008); A1;,
Pyridazine – Wikipedia
Pyridazine | C4H4N2 – PubChem

With the rapid development and complex challenges of chemical substances, new drug synthesis pathways are usually the most effective.70952-62-4,3,6-Dichloro-4-methoxypyridazine,as a common compound, the synthetic route is as follows.

5.87 g (39.1 mmol) of 2-tert-butylphenol, dimethylsulfoxide (80 mL) and 4.38 g (39.0 mmol) of potassium t-butoxide were mixed, and the mixture was stirred at room temperature for 20 minutes. To the mixture was added a dimethylsulfoxide solution (60 mL) containing 6.92 g (38.7 mmol) of 3,6-dichloro-4-methoxypyridazine, and the resulting mixture was stirred at room temperature for 40 minutes, and at 80C for 45 minutes. The reaction mixture was poured into a saturated aqueous ammonium chloride solution, and extracted with ethyl acetate. The organic layers were combined, washed with water, and then, with brine, and dried over anhydrous sodium sulfate. The solvent was removed, and the residue was purified by silica gel column chromatography (available from Merck Co., 9385, hexane:ethyl acetate, gradient) to obtain 2.66 g (9.09 mmol, Yield: 23.5%) of 3-(2-tert-butylphenoxy)-6-chloro-4-methoxypyridazine and 1.82 g (6.22 mmol, Yield: 16.1%) of 6-(2-tert-butylphenoxy)-3-chloro-4-methoxypyridazine.

The synthetic route of 70952-62-4 has been constantly updated, and we look forward to future research findings.

Reference£º
Patent; Sankyo Agro Company, Limited; EP1426365; (2004); A1;,
Pyridazine – Wikipedia
Pyridazine | C4H4N2 – PubChem

144294-43-9, 3-Amino-5-methylpyridazine is a pyridazine compound, ?involved in a variety of chemical synthesis. Rlated chemical reaction is continuously updated

Step 1: Preparation of 4,6-dibromo-5-methylpyridazin-3-amine A solution of Br2 (9.6 g, 60.07 mmol) in methanol (30 mL) was added dropwise into the mixture of 5-methylpyridazin-3-amine (3 g, 27.49 mmol), methanol (100 mL), and sodium bicarbonate (11.5 g, 136.89 mmol) at 0 C. The resulting solution was stirred for 2 h at room temperature, diluted with water, extracted with ethyl acetate, dried over sodium sulfate, and concentrated under vacuum. The residue was purified by a silica gel column eluting with ethyl acetate/petroleum ether (1/4) to afford the title compound (4.0 g, 55%) as a brown solid. LCMS [M+H+] 266.

The synthetic route of 144294-43-9 has been constantly updated, and we look forward to future research findings.

Reference£º
Patent; Genentech, Inc.; Terrett, Jack Alexander; Chen, Huifen; Constantineau-Forget, Lea; Larouche-Gauthier, Robin; Lepissier, Luce; Beaumier, Francis; Dery, Martin; Grand-Maitre, Chantal; Sturino, Claudio; Volgraf, Matthew; Villemure, Elisia; (138 pag.)US2019/284179; (2019); A1;,
Pyridazine – Wikipedia
Pyridazine | C4H4N2 – PubChem

With the rapid development and complex challenges of chemical substances, new drug synthesis pathways are usually the most effective.84956-71-8,2-(tert-Butyl)-4,5-dichloropyridazin-3(2H)-one,as a common compound, the synthetic route is as follows.

A solution of the product of part A (0.105 g, 0.300 mmol) in 2-fluoroethanol (1.75 mL) was treated with 11.4 mg p-toluenesulfonic acid hydrate (0.06 mmol; 20 mol %) in one portion at ambient temperature. After 24 h, all volatiles were removed in vacuo, and the residue directly purified by chromatography on silica (30*185 mm) using 4:1 hexanes/ethyl acetate. The main product peak eluting 360-450 mL was collected, pooled and concentrated in vacuo to a colorless oil (81.2 mg, 0.205 mmol; 68.3%). 1H NMR: (300 MHz, DMSO-d6) delta 8.28 (1H, s), 7.55-7.39 (4H, m), 5.44 (2H, s), 4.62-4.52 (1H, m), 4.47-4.36 (1H, m), 3.46-3.34 (1H, m), 3.36-3.25 (1H, m), 1.58 (9H, s), 1.49 (6H, s). 19F NMR: (282 MHz, DMSO-d6) delta -222.01 (1F, tt, J=47.8, 30.6 Hz). 13C NMR: (75 MHz, DMSO-d6) delta 157.8, 153.9, 146.3, 133.9, 127.7, 126.1, 125.8, 115.5, 83.17 (d, J=166.3 Hz), 76.3, 71.2, 65.3, 61.89 (d, J=19.2 Hz), 28.0, 27.4. HRMS Calcd. for C20H2635ClFN2O3 (M+H): 397.1689. found: 397.1695. TLC: Rf 0.51 (silica gel, 3:2 hexanes/ethyl acetate, uv).

84956-71-8 2-(tert-Butyl)-4,5-dichloropyridazin-3(2H)-one 2782225, apyridazine compound, is more and more widely used in various.

Reference£º
Patent; Lantheus Medical Imaging, Inc.; Cesati, Richard R.; Radeke, Heike S.; Pandey, Suresh K.; Purohit, Ajay; Robinson, Simon P.; US2015/196672; (2015); A1;,
Pyridazine – Wikipedia
Pyridazine | C4H4N2 – PubChem

1121-79-5, 3-Chloro-6-methylpyridazine is a pyridazine compound, ?involved in a variety of chemical synthesis. Rlated chemical reaction is continuously updated

Step 1. 3-Chloro-6-chloromethyl-pyridazine To a solution of 3-chloro-6-methyl-pyridazine (25 g, 0.2 mol) in chloroform (850 mL) at 60 C. was added trichloroisocyanuric acid (0.4 equivalent, 18.1 mol) and stirred for 15 hours. An additional charge of trichloroisocyanuric acid (3 g) was added and the mixture heated for an additional hour. The mixture was then cooled in an ice bath and filtered over celite. The organic solution was concentrated to a yellow oil which darkened and solidified upon standing in the freezer (yield 30 g, 95%).

The synthetic route of 1121-79-5 has been constantly updated, and we look forward to future research findings.

Reference£º
Patent; Genelabs Technologies, Inc.; US2009/226398; (2009); A1;,
Pyridazine – Wikipedia
Pyridazine | C4H4N2 – PubChem

88497-27-2, 3-Amino-6-bromopyridazine is a pyridazine compound, ?involved in a variety of chemical synthesis. Rlated chemical reaction is continuously updated

[00268] To a solution of amino-heterocycle derivative (1 eq.) in nBuOH under argon are added successively the aldehyde RzCHO (2.5 eq.), MgC^ (0.04 eq.) and 1,1,3,3-tetramethylbutyl isocyanide (1.15 eq.). The reaction mixture is heated at 130 C from between 3.5 h to overnight, and then concentrated in vacuo. The residue is partitioned between heptane and water, stirred for 15 to 40 min, the biphasic solution is filtered on Celpure P65, and the cake is washed with heptane. The two layers of the filtrate are separated, the organic layer is washed successively with water, an aqueous 1M NaOH and brine, then dried over Na2S04 and concentrated in vacuo to afford the expected amine which is used directly in the next step.

The synthetic route of 88497-27-2 has been constantly updated, and we look forward to future research findings.

Reference£º
Patent; GALAPAGOS NV; DESROY, Nicolas; HECKMANN, Bertrand; BRYS, Reginald Christophe Xavier; JONCOUR, Agnes Marie; PEIXOTO, Christophe; BOCK, Xavier Marie; HOUSSEMAN, Christopher Gaetan; WO2014/202458; (2014); A1;,
Pyridazine – Wikipedia
Pyridazine | C4H4N2 – PubChem

14161-11-6, 3,4,5-Trichloropyridazine is a pyridazine compound, ?involved in a variety of chemical synthesis. Rlated chemical reaction is continuously updated

A mixture of 3,4,5-trichloropyridazine (0.50 g, 2.73 mmol), 1-(4- fluorophenyl)piperazine (0.511 g, 2.83 mmol), and potassium carbonate (0.79 1 g, 5.72 mmol) in dioxane (10 ml) was heated to reflux for 1 h. The mixture was cooledand 35% hydrazine (4.94 ml, 54.5 mmol) was added. The mixture was heated to reflux for 16 h overnight. The reaction was diluted with ethyl acetate and water. The ethyl acetate layer was washed with water, dried over magnesium sulfate, and concentrated to give 4-chloro-5-(4-(4-fluorophenyl)piperazin- 1 -yl)-3 – hydrazinylpyridazine (0.880 g, 100%), which was used without purification. LCMS:

The synthetic route of 14161-11-6 has been constantly updated, and we look forward to future research findings.

Reference£º
Patent; BRISTOL-MYERS SQUIBB COMPANY; MATTSON, Ronald J.; MENG, Zhaoxing; GUERNON, Leatte R.; WO2013/192306; (2013); A1;,
Pyridazine – Wikipedia
Pyridazine | C4H4N2 – PubChem

1121-79-5, 3-Chloro-6-methylpyridazine is a pyridazine compound, ?involved in a variety of chemical synthesis. Rlated chemical reaction is continuously updated

PREPARATION 2 SYNTHESIS OF 6-CHLOROPYRIDAZINE-3-CARBOXYLIC ACID To a mechanically stirred solution of 3-chloro-6-methylpyridazine (155.6 mmol) in 140 mL of concentrated sulfuric acid, finely powdered potassium dichromate (55.40 g) was added slowly, the temperature being kept below 50 C. When the addition was complete, stirring was continued for another 4 hours at 50 C. The viscous, dark green liquid was then cooled and crushed ice was added cautiously. The reaction mixture was extracted with ethyl acetate (6 x 400 mL). The ethyl acetate extracts were combined, dried over anhydrous Na2SO4. The solvent was concentrated in vacuo to yield slightly red colored 6-chloropyridazine-3-carboxylic acid (106.6 mmol). This material was used for next reaction without further purification. Yield 69%. m.p. 145C (dec). 1H NMR (300 MHz, DMSO-d6) delta 13.1, 8.20, 8.05.

1121-79-5 3-Chloro-6-methylpyridazine 227254, apyridazine compound, is more and more widely used in various.

Reference£º
Patent; Xenon Pharmaceuticals Inc.; Abreo, Melwyn; Chafev, Mikhail; Chakka, Nagasree; Chowdhury, Sultan; Fu, Jian-Min; Gschwend, Heinz, W.; Holladay, Mark, W.; Hou, Duanjie; Kamboj, Rajender; Kodumuru, Vishnumurthy; Li, Wenbao; Liu, Shifeng; Raina, Vandna; Sun, Sengen; Sun, Shaoyi; Sviridov, Serguei; Tu, Chi; Winther, Michael, D.; Zhang, Zaihui; (94 pag.)EP2316827; (2016); B1;,
Pyridazine – Wikipedia
Pyridazine | C4H4N2 – PubChem