文摘
A "one pot" synthesis of new 2,6-diimine-4-alkylpyridines is reported. The addition of 2,6-[2,6-iPr2C6H3N=C(Me)]2C5H3N to the preformed MnR2(THF)n (R = CH2CMe2Ph,CH2Ph, CH2CH=CH2), followed by hydrolysis affords a mixtureof 4-alkyl 2,6-bis(imino) derivatives of pyridine and 1,4-dihydropyridine in a variable ratio. Treatment of the mixturewith a substoichiometric amount of CrO3/K2CO3 in THFprovides the 4-alkyl-2,6-diiminopyridines in good isolated yieldsand in a highly selective manner.