Category: 17635-44-8

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. 17635-44-8, name is 3,4,5-Tribromopyrazole, A new synthetic method of this compound is introduced below., Application In Synthesis of 3,4,5-Tribromopyrazole

To a solution of 3,4,5-tribromo-lH-pyrazole (25 g, 82 mmol, 1.0 eq) in THF (300 ml), was added n-BuLi (2.5 M in hexanes, 82.0 ml, 205 mmol, 2.5 eq) over 30 min at -78C and the RM was stirred at this temperature for 1.5 h. The RM was quenched by dropwise addition of MeOH-THF (2:3; 150 ml) at -78C, stirred for an additional 2 h gradually allowing it to warm to RT. Then, the solvent was removed under reduced pressure. The residue was diluted with diethyl ether (600 ml), washed with dil. HC1 (0.5 N, 60 ml) and brine (75 ml), dried (Na2S04), filtered and concentrated under reduced pressure to afford the title compound (18 g).

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.

Reference:
Patent; GRUeNENTHAL GMBH; SCHUNK, Stephan; REICH, Melanie; KOENIGS, Rene, Michael; (72 pag.)WO2017/59966; (2017); A1;,
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics

17635-44-8, name is 3,4,5-Tribromopyrazole, 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. Computed Properties of C3HBr3N2

EXAMPLE 2 Preparation of 3,4,5-Tribromopyrazole-1-propionic Acid A mixture consisting of 9.1 gm. (0.03 mole) 3,4,5-tribromopyrazole and 8.1 gm. (0.045 mole) ethyl 3-bromopropionate was heated at 140 C. for 24 hrs. in an atmosphere of nitrogen. After cooling, 80 ml. 0.5 N aqueous sodium hydroxide was added to the reaction mixture and it was heated at the reflux temperature for 3 hrs. After cooling again and adding 1 N aqueous hydrochloric acid until the mixture was pH 2, a precipitate formed. The precipitate was collected on a filter and recrystallized from a mixture of ether and technical hexane. There was thus obtained 10.1 gm. of 3,4,5-tribromopyrazole-1-propionic acid having a melting point at 112 to 113 C. Analysis: Calc’d. for C6 H5 Br3 N2 O2: C, 19.12; H, 1.33; N, 7.43; Br, 63.61. Found: C, 19.31; H, 1.54; N, 7.44; Br, 64.05.

The synthetic route of 17635-44-8 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. 17635-44-8, name is 3,4,5-Tribromopyrazole, A new synthetic method of this compound is introduced below., Formula: C3HBr3N2

EXAMPLE 30 Preparation of 3,4,5-Tribromo-alpha-methylpyrazole-1-acetic acid A quantity (3.04 gm., 0.01 mole) of 3,4,5-tribromopyrazole was dissolved in 70 ml. acetone and 2.76 gm. (0.02 mole) solid anhydrous potassium carbonate was added. The mixture was heated at the reflux temperature with stirring for 10 minutes and, after cooling, 2.0 gm. (0.011 mole) ethyl 2-bromopropionate was added. This reaction mixture was heated at the reflux temperature for 11/2 hrs. After cooling, an aqueous solution of sodium hydroxide (0.5 gm. in 90 ml. water) was added. The acetone was distilled off and the remaining aqueous solution was heated at the reflux temperature for 2 hrs. The clear solution thus obtained was cooled and acidified to about pH 2 with 2 N hydrochloric acid. A white precipitate that formed was collected on a filter, washed with water, and dried. There was thus obtained 3.55 gm. (95% yield) of 3,4,5-tribromo-alpha-methylpyrazole-1-acetic acid having a melting point at 162 to 164 C., identical with the product of Example 5.

The synthetic route of 17635-44-8 has been constantly updated, and we look forward to future research findings.

Adding a certain compound to certain chemical reactions, such as: 17635-44-8, name is 3,4,5-Tribromopyrazole, belongs to pyrazoles-derivatives compound, 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 17635-44-8, 17635-44-8

EXAMPLE 1 Preparation of Ethyl 3,4,5-Tribromopyrazole-1-acetate A quantity (92 gm., 0.3 mole) 3,4,5-tribromopyrazole was added with vigorous stirring to a solution of 7.1 gm. sodium (0.31 mole) in 300 ml. absolute ethanol. After the mixing was complete, 100 gm. (0.6 mole) ethyl bromoacetate was added dropwise while stirring was continued. The mixture was diluted with 200 ml. absolute ethanol and this reaction mixture was stirred at about 25 C. for about 18 hrs. After removing most of the ethanol by evaporation under reduced pressure, 100 ml. of 6 N hydrochloric acid was added to the residue, and this aqueous acid mixture was made alkaline with solid sodium carbonate. The aqueous layer was separated and extracted with three 60-ml, portions of ether. The ether extracts were combined, washed with three 40-ml. portions of water, and dried with anhydrous magnesium sulfate. After removing the ether by evaporation under reduced pressure, there was obtained a white solid. Recrystallization from technical hexane (Skellysolve B, a mixture of isomeric hexanes having a boiling range between 61 C. and 69 C.) gave 96.0 gm. of ethyl 3,4,5-tribromopyrazole-1-acetate having a melting point at 101 to 103 C. Analysis: Calc’d. for C7 H7 Br3 N2 O2: C, 21.51; H, 1.81; N, 7.17; Br, 61.33. Found: C, 21.79; H, 1.62; N, 6.96; Br, 61.56.

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, 3,4,5-Tribromopyrazole, other downstream synthetic routes, hurry up and to see.

17635-44-8, 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 17635-44-8 as follows.

The bromopyrazole 1c was prepared according to the published procedure [19]. Single crystals of (1c)2?HBr were grown from the reaction mixture at r. t. In a second crop crystals containing 1c, HBr, and Br2 in the ratio of 1 : 1 : 0.5 were obtained from this solution at r. t.

According to the analysis of related databases, 3,4,5-Tribromopyrazole, the application of this compound in the production field has become more and more popular.

17635-44-8, name is 3,4,5-Tribromopyrazole, 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. 17635-44-8

EXAMPLE 44 Preparation of 3,4,5-Tribromopyrazole-1-acetonitrile To a suspension of sodium hydride (2.2 gm. of a 60.6% dispersion in mineral oil, containing 0.055 mole of sodium hydride) in 60 ml. toluene was added a solution of 3,4,5-tribromopyrazole (15.2 gm., 0.05 mole) in 400 ml. hot toluene, followed by the dropwise addition of chloroacetonitrile (4.2 gm., 0.055 mole). The mixture was heated at the reflux temperature for 3 hrs. and then allowed to stand at about 25 C. for 18 hrs. Water (50 ml.) was added. The toluene layer was separated, washed with two 80-ml. portions of water, and dried with anhydrous sodium sulfate. Removal of the toluene gave 14.4 g. of 3,4,5-tribromopyrazole-1-acetonitrile as a white solid which was recrystallized from a mixture of ether and technical hexane.

Statistics shows that 17635-44-8 is playing an increasingly important role. we look forward to future research findings about 3,4,5-Tribromopyrazole.