Cesium carbonate → Tert-butyl (4-((6-nitropyridin-3-yl)oxy)pyridin-2-yl)carbamate

Participants

Reaction Conditions

Reaction Steps

A solution of Example A1 (1.5 g, 5.96 mmol) in dioxane (50 mL) was sparged with Ar, treated with tert-butyl carbamate (1.536 g, 13.11 mmol), Cs2CO3 (3.88 g, 11.92 mmol) and DPPF (0.420 g, 0.775 mmol), sparged with Ar, treated with Pd2(dba)3 (0.382 g, 0.417 mmol), sparged again with Ar and heated at 100° C. overnight. The mixture was cooled to RT, diluted with EtOAc, the solids removed via filtration through diatomaceous earth and washed with EtOAc. The filtrate was concentrated to dryness, treated with MeCN, sonicated and the solid collected via filtration. The filtrate was concentrated to dryness, treated again with MeCN and the solid collected. The filtrate was again concentrated to dryness, purified via silica gel chromatography (EtOAc/Hex) and combined with the two above-isolated solids to afford tert-butyl (4-((6-nitropyridin-3-yl)oxy)pyridin-2-yl)carbamate (1.5 g, 76%). MS (ESI) m/z: 333.1 (M+H+).

Provenance & Evidence