4-Bromo-1H-Indazole

4-Bromo-1H-Indazole - Names and Identifiers

Name	4-Bromo (1H)Indazole
Synonyms	4-Bromoindazole 4-BROMOINDAZOLE broMo-1H-indazole 4-Bromo(1H)Indazole 4-Bromo-1H-Indazole 4-BROMO (1H)INDAZOLE 4-Bromo (1H)Indazole 1H-Indazole, 4-bromo- 4-BROMO (1H)INDAZOLE fandachem 4-bromo-1H-indazole￡4-Bromoindazole
CAS	186407-74-9
EINECS	803-241-7
InChI	InChI=1/C7H5BrN2/c8-6-2-1-3-7-5(6)4-9-10-7/h1-4H,(H,9,10)
InChIKey	KJIODOACRIRBPB-UHFFFAOYSA-N

4-Bromo-1H-Indazole - Physico-chemical Properties

Molecular Formula	C7H5BrN2
Molar Mass	197.03
Density	1.770±0.06 g/cm3(Predicted)
Melting Point	165-167°
Boling Point	333.8±15.0 °C(Predicted)
Flash Point	155.69°C
Solubility	soluble in Ethanol
Vapor Presure	0mmHg at 25°C
Appearance	Brown powder
Color	Off-white
pKa	12.78±0.40(Predicted)
Storage Condition	2-8°C
Refractive Index	1.728
MDL	MFCD05664001
Physical and Chemical Properties	Brown solid

4-Bromo-1H-Indazole - Risk and Safety

Risk Codes	R25 - Toxic if swallowed R36/37/38 - Irritating to eyes, respiratory system and skin.
Safety Description	S26 - In case of contact with eyes, rinse immediately with plenty of water and seek medical advice. S45 - In case of accident or if you feel unwell, seek medical advice immediately (show the label whenever possible.)
UN IDs	2811
WGK Germany	3
Hazard Class	6.1
Packing Group	Ⅲ

4-Bromo-1H-Indazole - Reference Information

use

4-bromo-1H-indazole is a pharmaceutical intermediate that can be used to prepare dual inhibitors of RAS/RAF/MEK/ERK and PI3K/AKT/PTEN/MTOR pathways, such as 1-(tetrahydro-2H-pyran-2-yl)-4-(4,4,5, 5-Tetramethyl-1, 3, 2-dioxacyclopentaboran-2-yl)-1H-indazole.

Preparation

4-bromo-1H-indazole can be prepared from 1-bromo-3-fluorobenzene as raw material. 2-bromo-6-fluorobenzaldehyde, and then the ring is closed to prepare 4-bromo-1H-indazole.
step 1:2-bromo -6-fluorobenzaldehyde
n-butyl lithium (1.6M hexane)(3.56mL,0.00571mol) is added dropwise to the stirred diisopropylamine (1.4mL,0.00571mol) in the solution of dry tetrahydrofuran (7.2mL) at 0 ℃, and the stirring is continued at 0 ℃ for 15min. The reaction mixture was cooled to -78°C and 1-bromo-3-fluorobenzene (1g,0.00571mol) was added within 10min. After stirring at -78 ℃ for 1h, anhydrous N,N-dimethylformamide (7.2mL) was added dropwise within 5min, and the obtained mixture was stirred at -78 ℃ for another 20min. The reaction was quenched by the addition of acetic acid (0.6mL) followed by water (15mL) and the mixture was warmed to room temperature. The mixture was extracted using ethyl acetate (2x 20mL), and the combined organic layer was washed with water (2x 10mL), followed by brine, and dried on anhydrous sodium sulfate. The solvent was evaporated under vacuum to produce the title compound (850mg,73%) as a pale yellow solid.
Step 2: 4-Bromo-1H-indazole
Hydrazine hydrate (4.5mL) was added to the stirred solution of 2-bromo-6-fluorobenzaldehyde (850mg,0.004mol) in DMSO(1mL) at room temperature, and the resulting mixture was stirred overnight at 80°C. The reaction mixture was cooled to room temperature, water (10mL) was added, and the mixture was extracted with ethyl acetate (2 × 100mL). Wash the combined organic layer with brine solution, dry and filter on anhydrous sodium sulfate. The filtrate was evaporated under reduced pressure to produce the title compound (700mg,84%) as a yellow solid. %).

Last Update：2024-04-09 19:05:10