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The preparation of difluoropyridines by the Schiemann reaction was investigated. 2-Amino-6-fluoropyridine (Ilia), necessary for the synthesis of 2,6-difluoropyridine (IVa) by the Schiemann reaction, was conveniently prepared by the Curtius degradation of 6-fluoropicolinic hydrazide (Ha) and by the Hofmann reaction on 6-fluoropicolinamide (lid). Since an «-fluorine on a pyridine nucleus is preferentially replaced by hydrazine when it is either adjacent to or opposite a carbomethoxy group, the hydrazides necessary for the synthesis of 3-amino-2and 6-fluoropyridine could not be prepared. These amines were prepared from the appropriate 2-fluoropyridinecarboxamide by the Hofmann reaction. The preparation of difluoropyridines was successful with two of the aminofluoropyridines and led to the following new compounds: 2,3-difluoro-(IVb) and 2,6-difluoropyridine (IVa).The chemistry of nuclear fluorinated pyridines has been limited to the monofluoropyridines,6 their derivatives,6 and pentafluoropyridine.7 As information on the other polyfluoropyridines was needed, our attention was directed to the difluoropyridines. This communication describes the preparation of 2,6-difluoropyridine (IVa),8 2,3-difluoropyridine (IVb), and the attempted synthesis of 2.5-difluoropyridine.The reaction scheme selected for the synthesis of 2.6-difluoropyridine (IVa), based on a related reaction sequence originally used to prepare 2-amino-6chloropyridine,9 is outlined as illustrated. The F CO2CH3

Methods previously employed in the synthesis of l,3-dihydroxy-3-methyl-2-pentanone (III) failed when applied to 1,3dihydroxy-3-phenyl-2-butanone (X). Because of this, a study of other ester intermediates which might be employed in this synthesis, was undertaken. l-(p-Hydroxybenzoates) could not be converted readily to dihydroxyacetones; however, hydrolysis of the l-(p-nitrobenzoate) and l-(p-chlorobenzoate) of X led to the synthesis of the desired l,3-dihydroxy-3-phenyl-