Day: March 9, 2022

With the rapid development and complex challenges of chemical substances, the synthesis of new drugs is usually one of the most effective ways to increase yield.55405-67-9, name is 3-Bromopyrazolo[1,5-a]pyrimidine, molecular formula is C6H4BrN3, molecular weight is 198.0201, as common compound, the synthetic route is as follows.COA of Formula: C6H4BrN3

To a stirred solution of compound 13f (27.8 mmol) in 1,4-dioxane (120 mL) was added B2Pm2 (126 mmol) and KOAc (101 mmol) at rt. The resulting mixture was purged with Ar for 45min, PdCl2(PPli3)2 (1.5 mmol) was added and the mixture again purged with Ar for 30min. The resulting mixture was heated to 1000C for 15h. The reaction mixture was concentrated to obtain a viscous mass, which was charged over afluorosil plug, washed with pentane, followed by 60% EtOAc/Pet ether. The relevant fractions were concentrated to obtain a crude compound 13g as a pale yellow solid. The crude compound 13g was stirred with pentane (25mL) at -400C for 30min, filtered, washed with cold pentane (5mL) and dried under vacuum to obtain sufficiently pure compound (3.5g, 51.4%). TLC system: Ethyl acetate: Petroleum ether (2:3) Rf value: 0.4. (M + H): 246.3.

At the same time, in my other blogs, there are other synthetic methods of this type of compound,55405-67-9, 3-Bromopyrazolo[1,5-a]pyrimidine, and friends who are interested can also refer to it.

Reference:
Patent; VERTEX PHARMACEUTICALS INCORPORATED; WO2009/85913; (2009); A1;,
Pyrimidine | C4H4N2 – PubChem,
Pyrimidine – Wikipedia

Reference of 1801-06-5 ,Some common heterocyclic compound, 1801-06-5, molecular formula is C5H4ClFN2O, 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 100 ml dichloroethane and 25 ml acetonitrile as a solvent. Using dichloroethane as a solvent, the first 100 ml dichloroethane and 25 ml acetonitrile is poured into the 250 ml flask is, by adding 14.4g (0.1mol) of 2-methoxy-5-fluoro-4-hydroxy-pyrimidine. After dropwise 32.2g (0.3mol) of phosphorus oxychloride, within half an hour after the dropping, the stirring 10 minutes later, start dropwise triethylamine 21.2g (0.21mol), heating to 60 °C, stirring 2 hours later, cooling. In the reaction solution is poured into the crushed ice, to be layered. Applying the organic phase is 2-methoxy-4-chloro-5-fluoro pyrimidine dichloroethane solution.Then, 15 g of hydrazine hydrate were added dropwise thereto, and the mixture was heated to 70 ° C and reacted 2h, and the reaction was monitored by HPLC. The product was obtained as white needle crystals. 2-Methoxy-4-hydrazino-5-fluoro pyrimidine 11.98g (0.075 mol), m.p. 187 ° -188 ° C, product content 98.5percent, yield 77percent.

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. 1801-06-5, 4-Chloro-5-fluoro-2-methoxypyrimidine, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; Shenyang Sinochem Pesticide Chemical R & D Co., Ltd; Cao, Wei; Sun, Ke; Guan, Yunfei; Pei, Heying; Li, Yanjuan; (6 pag.)CN105801492; (2016); A;,
Pyrimidine | C4H4N2 – PubChem,
Pyrimidine – Wikipedia

Synthetic Route of 69696-37-3 , The common heterocyclic compound, 69696-37-3, name is 5-Bromo-2,4-dimethylpyrimidine, molecular formula is C6H7BrN2, 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 tetrahydropyran-4- amine (1.35 g, 13.4 mmol) in toluene (5 ml) was added 5-bromo-2,4- dimethyl-pyrimidine (500 mg, 2.67 mmol), BINAP (333 mg, 0.53 mmol), Cs2C03 (1.74 g, 5.35 mmol) and Pd(OAc)2 (60 mg, 0.27 mmol) at rt under N2. The mixture was heated at 120 C for 3 h under a N2 atmosphere. H20 (10 ml) was added and the mixture was extracted with EtOAc (3 x 10 ml). The combined organic layers were washed with brine (5 ml), dried over Na2S04, filtered and concentrated under reduced pressure to give a residue. The residue was purified by FCC (0 – 50 % MeOH in EtOAc) to give the title compound as a brown solid (Y = (1619) 90 %). H NMR (400 MHz, methanol-^) d ppm 7.98 (s, 1H), 4.02 – 3.99 (m, 2H), 3.62 – 3.54 (m, 3H), 2.51 (s, 3H), 2.39 (s, 3H), 2.05 – 1.92 (m, 2H), 1.66 – 1.56 (m, 2H).

The synthetic route of 69696-37-3 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; NODTHERA LIMITED; HARRISON, David; WATT, Alan Paul; BOCK, Mark G.; (334 pag.)WO2019/121691; (2019); A1;,
Pyrimidine | C4H4N2 – PubChem,
Pyrimidine – Wikipedia

Electric Literature of 69205-79-4, In the chemical reaction process,reaction time,type of solvent,can easily affect the result of the reaction, thereby determining the yield and properties of the reaction product.An updated downstream synthesis route of 69205-79-4 as follows.

Anew synthesis of 7-formyl-preQ0 (systematic name, 2-amino-5-formylpyrrolo[2,3-d]pyrimidin-4-one) that, contrary to literature-known procedures (21-23), does not require protecting group chemistry was developed. PreQ0 (808 mg, 4.61 mmol)and sodium hypophosphite dihydrate (1.44 g, 13.6 mmol) were dissolved in the solvent mixture (15 ml of pyridine/acetic acid/deionized water in a ratio of 2:1:1) and stirred under inert atmosphere.Raney nickel catalyst (slurry in water, 500 mg) wasadded to the stirred reaction mixture. Safety precaution: dryRaney nickel is pyrophoric and should always be handled underinert atmosphere. The resulting reaction mixture was heated to50 C for 5 h. Subsequently, the reaction mixture was cooled to room temperature and filtered over a pad of celite. The filtrate was reduced in vacuo. The remaining brown residue was dissolvedin 6 M aqueous potassium hydroxide solution. The remaining solids were filtered off. The filtrate was cooled to 0 Cand neutralized by addition of concentrated aqueous HCl. Theproduct precipitated from the solution and was isolated by filtrationand washed with copious amounts of ice water and acetone(brown solid, 770 mg, 94%). 1H NMR (DMSO-d6) 6.35(bs, 2H, NH2), 7.49 (s, 1H, H-8), 10.04 (s, 1H, CHO), 10.72 (bs,1H, H-9), 11.96 (bs, 1H, H-1); 13C NMR (DMSO-d6) 98.36(C-7), 120.34 (C-8), 124.50 (C-5), 153.40 (C-2), 153.83 (C-4),159.02 (C-6), 185.47 (CHO). NMR data were recorded on aBruker AVANCE III with autosampler (1H NMR 300.36 MHz,13C NMR 75.53 MHz).

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route,69205-79-4, its application will become more common.

Reference:
Article; Jung, Jihye; Czabany, Tibor; Wilding, Birgit; Klempier, Norbert; Nidetzky, Bernd; Journal of Biological Chemistry; vol. 291; 49; (2016); p. 25411 – 25426;,
Pyrimidine | C4H4N2 – PubChem,
Pyrimidine – Wikipedia

Reference of 38275-43-3, 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. 38275-43-3, name is 2-(Methylthio)pyrimidine-5-carbonitrile, molecular formula is C6H5N3S, The 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.

To a mixture of 2-(methylsulfanyl)pyrimidine-5-carbonitrile (25.00 g, 165.35 mmol, 1.00 eq) and hydroxylamine hydrochloride (22.98 g, 330.70 mmol, 2.00 eq) in ethanol (250.00 ml) and water (250.00 ml) was added sodium hydrogen carbonate (27.78 g, 330.70 mmol, 2.00 eq). The reaction was stirred at 70 C for 16 h. This mixture was filtered and washed with water (50 ml*4). The residue was collected and evaporated. This residue N’-hydroxy-2-(methylsulfanyl)pyrimidine-5- carboximidamide (29.00 g, crude) was used for next step without further purification

According to the analysis of related databases, 38275-43-3, the application of this compound in the production field has become more and more popular.

Reference:
Patent; BAYER AKTIENGESELLSCHAFT; BAYER CROPSCIENCE AKTIENGESELLSCHAFT; BRUNET, Stephane; GOeRTZ, Andreas; GOURGUES, Mathieu; HILT, Emmanuelle; JAKOBI, Harald; NAUD, Sebastien; REBSTOCK, Anne-Sophie; DUCERF, Sophie; (78 pag.)WO2019/122323; (2019); A1;,
Pyrimidine | C4H4N2 – PubChem,
Pyrimidine – Wikipedia