| 95% |
With hydrogenchloride; tin(ll) chloride; In diethylene glycol dimethyl ether; water; at 0℃; for 0.583333h;Inert atmosphere; Cooling with ice; |
Intermediate Example 11 Preparation of 2,3-dimethyl-2H-indazol-6-amine To a stirred solution of 18.5 g (0.11 mol) of 3-methyl-6-nitro-1H-indazole in 350 ml acetone, at room temperature, was added 20 g (0.14 mol) of trimethyloxonium tetraflouroborate. After the solution was allowed to stir under argon for 3 hours, the solvent was removed under reduced pressure. To the resulting solid was added saturated aqueous NaHCO3 (600 ml) and a 4:1 mixture of chloroform-isopropanol (200 ml), and the mixture was agitated and the layers were separated. The aqueous phase was washed with additional chloroform: isopropanol (4 x 200 ml) and the combined organic phase was dried (Na2SO4). Filtration and removal of solvent gave a tan solid. The solid was washed with ether (200 ml) to afford 2,3-dimethyl-6-nitro-2H-indazole as a yellow solid (15.85 g, 73 %). 1H NMR (300 MHz, d6DMSO) delta 8.51 (s, 1H), 7.94 (d, J = 9.1 Hz, 1H), 7.73 (d, J = 8.9 Hz, 1H), 4.14 (s, 3H), 2.67 (s, 3H). MS (ES+, m/z) 192 (M+H).; To a stirred solution of 2,3-dimethyl-6-nitro-2H-indazole (1.13 g) in 2-methoxyethyl ether (12 ml), at 0 C, was added a solution of 4.48 g of tin(II) chloride in 8.9 ml of concentrated HCl dropwise over 5 min. After the addition was complete, the ice bath was removed and the solution was allowed to stir for an additional 30 min. Approximately 40 ml of diethyl ether was added to reaction, resulting in precipitate formation. The resulting precipitate was isolated by filtration and washed with diethyl ether, and afforded a yellow solid (1.1 g, 95 %), the HCl salt 2,3-dimethyl-2H-indazol-6-amine. 1H NMR (300 MHz, d6DMSO) delta 7.77 (d, J = 8.9 Hz, 1H), 7.18 (s, 1H), 7.88 (m, 1H), 4.04 (s, 3H), 2.61 (s, 3H). MS (ES+, m/z) 162 (M+H). |
| 95% |
With hydrogenchloride; tin(ll) chloride; In diethylene glycol dimethyl ether; water; at 0℃; for 0.583333h; |
Intermediate Example 2 Preparation of 2,3-dimethyl-6-amino-2H-indazole Procedure 1: To a stirred solution of 2,3-dimethyl-6-nitro-2H-indazole (1.13 g) in 2-methoxyethyl ether (12 ml), at 0 C., was added a solution of 4.48 g of tin(II) chloride in 8.9 ml of concentrated HCl dropwise over 5 min. After the addition was complete, the ice bath was removed and the solution was allowed to stir for an additional 30 min. Approximately 40 ml of diethyl ether was added to reaction, resulting in precipitate formation. The resulting precipitate was isolated by filtration and washed with diethyl ether, and afforded a yellow solid (1.1 g, 95%), the HCl salt 2,3-dimethyl-2H-indazol-6-amine. 1H NMR (300 MHz, DMSO-d6) delta 7.77 (d, J=8.9 Hz, 1H), 7.18 (s, 1H), 7.88 (m, 1H), 4.04 (s, 3H), 2.61 (s, 3H). MS (ES+, m/z) 162 (M+H). |
| 95% |
With hydrogenchloride; tin(ll) chloride; In diethylene glycol dimethyl ether; water; at 0℃; for 0.583333h; |
Intermediate Example 2 Preparation of 2,3-dimethyl-6-amino-2H-indazole Procedure 1: To a stirred solution of 2,3-dimethyl-6-nitro-2H-indazole (1.13 g) in 2- methoxyethyl ether (12 ml), at 0 C, was added a solution of 4.48 g of tin(II) chloride in 8.9 ml of concentrated HCI dropwise over 5 min. After the addition was complete, the ice bath was removed and the solution was allowed to stir for an additional 30 min. Approximately 40 ml of diethyl ether was added to reaction, resulting in precipitate formation. The resulting precipitate was isolated by filtration and washed with diethyl ether, and afforded a yellow solid (1.1 g, 95 %), the HCI salt 2,3-dimethyl-2H-indazol-6-amine. |
| 95% |
With hydrogenchloride; tin(ll) chloride; In diethylene glycol dimethyl ether; water; at 0℃; for 0.583333h; |
To a stirred solution of 2,3-dimethyl-6-nitro-2/-/-indazole (1.13 g) in 2- methoxyethyl ether (12 ml), at 0 0C, was added a solution of 4.48 g of tin(ll) chloride in 8.9 ml of concentrated HCI dropwise over 5 min. After the addition was complete, the ice bath was removed and the solution was allowed to stir for an additional 30 min. Approximately 40 ml of diethyl ether was added to reaction, resulting in precipitate formation. The resulting precipitate was isolated by filtration and washed with diethyl ether, and afforded a yellow solid (1.1 g, 95 %), the HCI salt 2,3-dimethyl-2H-indazol-6- amine. 1H NMR (300 MHz, DMSOd6) delta 7.77 (d, J = 8.9 Hz, 1 H), 7.18 (s, 1 H), 7.88 (m, 1 H), 4.04 (s, 3H), 2.61 (s, 3H). MS (ES+, m/z) 162 (M+H). |
| 95% |
With hydrogenchloride; tin(ll) chloride; In ethanol; water; at 0℃; |
After stirring and mixing a concentrated hydrochloric acid solution (80 mL) of stannous chloride (0.24 mol) at 0 C. with ethanol (150 mL)From Li E 10 into the third mixing valve 11, the flow rate of Li E 10 was 2.56 mL / min. At the same time, the second micro-reaction in step (2)The effluent 2,3-dimethyl-6-nitro-2H-indazole product (0.0216 mol) from the reactor 9 flows into the third mixing valve 11. Two stocksAfter fully mixed, it enters the third micro-reactor 12 in the second continuous micro-channel reaction device, reacts at room temperature, and the residence timeFor 7.6min, the second receiving device 13 collects the reaction effluent, the second receiving device 13 is a container for ethanol, the volume of ethanol1.5L, 2,3-dimethyl-2H-indazole-6-amine hydrochloride was precipitated, S was the product, and the yield was 95%. |
Chemistry
Pharmaceutical Intermediates
Inhibitors/Agonists
Material Science
For Research Only
120K+ Compounds
Competitive Price
1-2 Day Shipping
