Synthetic Route of 1192-21-8, A common heterocyclic compound, 1192-21-8, name is 1-Methyl-1H-pyrazol-5-amine, molecular formula is C4H7N3, its traditional synthetic route has been very mature, but the traditional synthetic route has various shortcomings, such as complicated route, low yield, poor purity, etc, below Introduce a new synthetic route.
in two screw-top glass pressure vessels, split and combine the following amounts in two equal portions 2-(2-chioro-4-pyridyi)-5-(2-nethoxyethyi)-6,6-dimethyi-thieno[2,3- c]pyrroi-4-one (13 g, 38.59 mmol), 1-methyi-5-aminopyrazole (11.245 g, 115.78 mmoi),cesium carbonate (37.724 g, 115.78 mrnol), 4,5-bis(diphenylphosphino)-9,9- dimethylxanthene (2.010 g, 3.47 mmoi), paiiadium(ii)acetate (520 mg, 2.32 nmoi) and 1,4-dioxane (350 mL). Seal each vessel and heat at 110 °C overnight.Dilute the reaction mixture with 10percent MeOH in DCM (2 L) and wash the resulting solution with saturated NaC1. Back extract the aqueous solution with DCM and combinethe organic solutions. Dry the combined solutions over a mixture of an hyous sodium sulfate and aithydrous magnesium sulfate, filter and concentrate the filtrate under reduced pressure. Purify by silica gel chromatography by loading the residue onto a 260 g loading coiunm with DCM and then eluting the loading coiunm onto a 750 g silica gel column with a gradient of 60-100percent of 10percent MeOH in EtOAc in hexane to yield the titlecompound 8.4 g (55percent). MS rn/z): 398 (M+i).
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; ELI LILLY AND COMPANY; CORTEZ, Guillermo S.; JOSEPH, Sajan; MCLEAN, Jonathan Alexander; MCMILLEN, William T.; RODRIGUEZ, Michael John; ZHAO, Gaiying; (70 pag.)WO2016/106009; (2016); A1;,
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