2002 pyridine derivatives

pyridine derivativesR 0380

02 - 156Regiospecific Synthesis of 4-(2-Oxoalkyl)pyridines. — A new methodfor the regioselective introduction of β-oxoalkyl groups into the 4-position ofpyridine is presented. Title compounds (V) are prepared in two steps viadihydropyridines (IV). In the first step, triflic anhydride is used to activate thepyridine ring to react with ketones (I). In the second step, under treatment ofthe dihydropyridines with tBuOK in DMSO, the triflate group is eliminated.This method complements the existing methods as it is highly regioselectiveand high-yielding. — (KATRITZKY, ALAN R.; ZHANG, SUOMING; KURZ,THOMAS; WANG, MINGYI; STEEL, PETER J.; Org. Lett. 3 (2001) 18,2807-2809; Dep. Chem., Cent. Heterocycl. Compd., Univ. Fla., Gainesville, FL32611, USA; EN)

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