Reference of 3528-45-8, In the next few decades, the world population will flourish. As the population grows rapidly and people all over the world use more and more resources, all industries must consider their environmental impact. 3528-45-8, name is 1-(4-Methoxybenzyl)-1H-pyrazol-5-amine belongs to pyrazoles-derivatives compound, it is a common compound, a new synthetic route is introduced below.
A stirred mixture of triethoxymethane (339 mL, 2037 mmol), and 2,2-dimethyl-1,3-dioxane-4,6-dione (Meldrum’s acid) (35.2 g, 244 mmol) was heated to 80 C. for 1 hour. A suspension of 1-(4-methoxybenzyl)-1H-pyrazol-5-amine [41.4 g, 204 mmol; prepared according to the procedure described by Misra, R. N., et al. Bioorg. Med. Chem. Lett. 2003, 13, 1133-1136, except desalting was performed as follows: 1-(4-methoxybenzyl)-1H-pyrazol-5-amine hydrochloride (44 g) was partitioned between MTBE (300 mL) and 1N aqueous NaOH (300 mL), after separating the phases, the aqueous suspension was re-extracted with MTBE (8×100 mL), followed by drying (Na2SO4) the combined organic phases, and concentration in vacuo to obtain the free-based 1-(4-methoxybenzyl)-1H-pyrazol-5-amine (30 g)] in triethoxymethane (339 mL, 2037 mmol) was added at once and heating at 80 C. was continued for 18 hours under N2. After cooling to room temperature, toluene azeotrope (2×200 mL) was utilized to remove EtOH. The resulting suspension was diluted with diethyl ether (500 mL) and filtered to obtain a yellow solid (33.5 g, 46%). 1H NMR (400 MHz, CDCl3) delta 11.13 (d, J=13 Hz, 1H), 8.26 (d, J=13 Hz, 1H), 7.50 (d, J=2 Hz, 1H), 7.25 (d, J=9 Hz, 2H), 6.88 (d, J=9 Hz, 2H), 6.21 (d, J=2 Hz, 1H), 5.28 (s, 2H), 3.78 (s, 3H), 1.74 (s, 6H).
The synthetic route of 1-(4-Methoxybenzyl)-1H-pyrazol-5-amine has been constantly updated, and we look forward to future research findings.
Reference:
Patent; Blake, James F.; Boyd, Steven Armen; De Meese, Jason; Fong, Kin Chiu; Gaudino, John J.; Kaplan, Tomas; Marlow, Allison L.; Seo, Jeongbeob; Thomas, Allen A.; Tian, Hongqi; Cohen, Frederick; Young, Wendy B.; US2007/238726; (2007); A1;,
Pyrazole – Wikipedia,
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