Pyridine → methyl 4-(3-bromo-4-fluorophenyl)-2-(bromomethyl)-5-oxo-4,5,6,8-tetrahydro-1H-pyrano[3,4-b]pyridine-3-carboxylate

Beteiligte Stoffe

Reaktionsschritte

A solution of the product from Example 25A (0.87 g, 2.2 mmol) in chloroform (10 mL) was cooled to −10° C., treated with pyridine (0.21 mL, 2.6 mmol), then treated with pyridinium tribromide (0.84 g, 2.6 mmol), stirred for 1 hour, diluted with methylene chloride (150 mL) and washed with 1N HCl (25 mL). The organic layer was dried (MgSO4), filtered and concentrated. The residue was purified by flash chromatography over silica gel (1% and then 2% methanol/methylene chloride) to provide the title compound (0.68 g) as an oil.

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