ChemicalBook CAS DataBase List 2-benzyl-4-bromoindazole

2-benzyl-4-bromoindazole synthesis

5synthesis methods

Product Name:2-benzyl-4-bromoindazole
CAS Number:952734-38-2
Molecular formula:C14H11BrN2
Molecular Weight:287.15

100-39-0
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$10.00/10g

186407-74-9 Synthesis

186407-74-9
312 suppliers
$5.00/1g

952734-38-2
21 suppliers
$454.60/5MG

Yield:952734-38-2 77%

Reaction Conditions:

in N,N-dimethyl-formamide at 50; for 25 h;

Steps:

4 2-N-benzyl-4-bromoindazole

Example 4 2-N-benzyl-4-bromoindazole 4-Bromoindazole of Example 2 (17.4 g, 0.088 M), benzyl bromide (22.7 g, 0.132 M) and DMF (35 mL) were heated to about 50° C. for 25 hours (HPLC: 15:1 ratio of 2-N and 1-N isomers). The mixture was cooled to ambient temperature and diluted with ethyl acetate (160 mL) and water (100 mL). The organic layer was separated, washed with aqueous sodium bicarbonate (5%, 100 mL). The organic layer was separated and concentrated under reduced pressure. The residue was diluted with isopropanol (160 mL) and concentrated under reduced pressure to a volume of about 120 mL. The mixture was heated to 50° C. to dissolve the solid and diluted with water (70 mL) to precipitate the product. The slurry was cooled to 0° C. and the precipitate was filtered off. The solid washed with a mixture of IPA and Water (1:1, 50 mL), and dried at 50° C. to provide the titled compound (16.5 g, 77%, which contained less than 2% of 1-N-isomer by HPLC): ¹H NMR (CDCl₃, δ, ppm) 5.56 (s, 2H), 7.11 (m, 1H), 7.21 (d, J=7.2 Hz, 1H), 7.24-7.39 (m, 5H), 7.65 (d, J=8.6 Hz, 1H), 7.88 (s, 1H).

References:

US2007/244178,2007,A1 Location in patent:Page/Page column 12

100-39-0
432 suppliers
$10.00/10g

186407-74-9 Synthesis

186407-74-9
312 suppliers
$5.00/1g

952734-38-2
21 suppliers
$454.60/5MG