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. 578008-32-9, name is tert-Butyl 3-amino-5-methyl-1H-pyrazole-1-carboxylate, A new synthetic method of this compound is introduced below., name: tert-Butyl 3-amino-5-methyl-1H-pyrazole-1-carboxylate
Step D: To 4-chloro-2-[difluoro-(5-fluoro-pyridin-2-yl)-methyl]-8-methylquinazoline (0.255 g, 0.79 mmol) in DMA (2 mL) were added 3-amino-5-methyl-pyrazole-1-carboxylic acid tert-butyl ester prepared according to US2007/219195 (0.31 g, 1.58 mmol) and acetic acid (0.15 mL) and the mixture was heated at 100 C. for 6.5 h. The mixture was allowed to cool to rt and then was purified by reverse phase HPLC using an ammonium acetate modifier. Fraction 1 containing pure product were combined, treated with saturated aq NaHCO3 and concentrated under reduced pressure. The aqueous residue was extracted with DCM and the combined extracts were washed with saturated aq NaHCO3 and brine, dried over MgSO4, filtered, and concentrated under reduced pressure to afford 2-(difluoro(5-fluoropyridin-2-yl)methyl)-8-methyl-N-(5-methyl-1H-pyrazol-3-yl)quinazolin-4-amine (28 mg, 13%). 1H NMR (300 MHz, DMSO-d6) delta 12.15 (br s, 1H), 10.57 (s, 1H), 8.67 (s, 1H), 8.50 (d, J=8.3 Hz, 1H), 7.92-8.11 (m, 2H), 7.75 (d, J=7.0 Hz, 1H), 7.52 (t, J=7.6 Hz, 1H), 5.96 (s, 1H), 2.59 (s, 3H), 2.17 (s, 3H); LC-MS (ESI) m/z 385 (M+H)+.
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; Hadd, Michael J.; Holladay, Mark W.; Rowbottom, Martin; US2012/53174; (2012); A1;,
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