Synthesis of [1, 2, 4]-triazolo [1, 5-a] pyrimidines by Dimroth rearrangement of [1, 2, 4]-triazolo [4, 3-a] pyrimidines: A theoretical and NMR study

…, F García, P Pevarello, I Alkorta, J Elguero

Index: Salgado, Antonio; Varela, Carmen; Garcia Collazo, Ana Maria; Garcia, Fernando; Pevarello, Paolo; Alkorta, Ibon; Elguero, Jose Journal of Molecular Structure, 2011 , vol. 987, # 1-3 p. 13 - 24

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Citation Number: 15

Abstract

Novel [1, 2, 4]-triazolo-[1, 5-a] pyrimidine derivatives were prepared by oxidative cyclization of suitable N-benzylidene-N′-pyrimidin-2-yl hydrazine precursors, followed by a Dimroth rearrangement. Reaction of 6-bromo-[1, 2, 4]-triazolo-[4, 3-a] pyrimidines with aliphatic amines under microwave irradiation gave the unexpected 5-amino compounds from an ANRORC-type mechanism. Full NMR and HRMS characterization was done for all the ...