Sodium Carbonate → 6'-(4-Methoxypyridin-2-yl)-2',2'-dimethyldispiro[1,3-oxazole-4,4'-chromene-3',3''-oxetan]-2-amine

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

A mixture of di-tert-butyl [2′,2′-dimethyl-6′-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)dispiro[1,3-oxazole-4,4′-chromene-3′,3″-oxetan]-2-yl]imidodicarbonate (282 mg, 0.470 mmol), 2-bromo-4-methoxypyridine (221 mg, 1.17 mmol), tetrakis(triphenylphosphine)palladium(0) (271 mg, 0.235 mmol) and Na2CO3 (149 mg, 1.41 mmol) in dioxane-water (4:1, 5.6 mL) was stirred for 8 hours at 100° C. The mixture was diluted with MeOH—CHCl3 (1:9) and washed with water, then the organic layer was dried over MgSO4 and filtered. The filtrate was concentrated at reduced pressure. To the residue were added toluene (2.8 mL) and silica gel (neutral; 846 mg), and the mixture was stirred for 3 hours at 120° C. After concentration of the reaction mixture at reduced pressure, the residue was purified with column chromatography on silica gel (CHCl3-EtOH, a linear gradient of EtOH from 0 to 20%) afforded 6′-(4-methoxypyridin-2-yl)-2′,2′-dimethyldispiro[1,3-oxazole-4,4′-chromene-3′,3″-oxetan]-2-amine (146 mg).

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