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  Lithium methoxide (3 cm3, 3mmol of 1.0M solution in methanol) was added to  (11) (1.0 g, 2.8 mmol) in methanol (15 cm3) at 0 °C, with stirring, under an atmosphere  of nitrogen. The mixture was stirred at room temperature for 67 h, then water (20 cm3)  was added and the mixture extracted into dichloromethane (DCM). The DCM solution  was dried (MgS04) and evaporated giving a solid ( 1.1 g) shown to consist of 4- methoxy-3,5-difluoro-2,6-dibromopyridine (22g) ( 19% ), 2,6-dibromo-4,5-dimethoxy-3- fluoropyridine (22h) (5%), (23b) (39% by comparison with authentic sample) and (23a)  (36%). Neither column chromatography (eluting DCM and petrol 7: 3) nor preparative  scale GLC ( 10% SE30, 140 oC) gave adequate separation of the products. However, a  carbon nmr spectrum and GCMS of a mixture of (22g) and (23b) was obtained and the  carbon spectra was assigned by comparison with that of (23b ).;

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