Research in the azole series. 103. Synthesis and 13C NMR study of pyrazole??4??carboxaldehydes

…, J Elguero, W Meutermans

Index: Echevarria, Aurea; Elguero, Jose; Meutermans, Wim Journal of Heterocyclic Chemistry, 1993 , vol. 30, # 4 p. 957 - 960

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Citation Number: 14

Abstract

Abstract Ten new pyrazoles have been prepared and their 13 C nmr chemical shifts compared with those of twelve other pyrazoles, some of them prepared purposely for this study. The chemical shifts are discussed statistically assuming that they are additive. A formyl group in the position 4 of the pyrazole ring produces a large effect on carbon C 4 (SCS= 17.3 ppm) and medium effects on carbons C 3 (SCS= 1.9 ppm) and C 5 (SCS= 3.8 ...