2-bromo-1-oxidopyridin-1-ium

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 2-Bromopyridine-N-oxide (28.36 g) was carefully dissolved in concentrated sulphuric acid (43 ml) with stirring. A mixture of concentrated sulphuric acid (65 ml) and concentrated nitric acid (43 ml) was added dropwise, and the mixture refluxed for 3 hours and allowed to cool to room temperature. The mixture was then poured on to ice and the precipitate removed by filtration , washed with water and air dried leaving a fine yellow powder of 2-Bromo-4-nitro-pyridine-N-oxide (14.08 g, 63%), m.p. 145-147° C. was added dropwise the mixture refluxed for 3 hours The mixture was then poured on to ice the precipitate removed by filtration washed with water and air dried

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A solution of 431 (460 mg, 0.94 mmol), 2-bromopyridine N-oxide (420 mg, 2.41 mmol), bistrimethyltin (294 μL, 465 mg, 1.42 mmol) and Pd(PPh3)4 (109 mg, 0.09 mmol) in dioxane (10 mL) was heated to reflux for 8 hrs under nitrogen. The reaction mixture was concentrated and purified by flash chromatography using the gradient 5-20% MeOH in EtOAc as an eluent yielding 432 (243 mg, 57% yield). LCMS: (M+H) 454.1. to reflux for 8 hrs under nitrogen The reaction mixture was concentrated purified by flash chromatography

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 2-Bromopyridine-N-oxide (28.36 g) was carefully dissolved in concentrated sulphuric acid (43 ml) with stirring. A mixture of concentrated sulphuric acid (65 ml) and concentrated nitric acid (43 ml) was added dropwise, and the mixture refluxed for 3 hours and allowed to cool to room temperature. The mixture was then poured on to ice and the precipitate removed by filtration , washed with water and air dried leaving a fine yellow powder of 2-Bromo-4-nitro-pyridine-N-oxide (14.08 g, 63%), m.p. 145-147° C. was added dropwise the mixture refluxed for 3 hours The mixture was then poured on to ice the precipitate removed by filtration washed with water and air dried