Long-range correlations ( n j C,H n > 3 ) in the HMBC spectra of 3-(4-oxo-4H-chromen-3-YL)-acrylic acid ethyl esters

Journal of the Brazilian Chemical Society

Ramiro Araya-maturana²  José A. Gavín-sazatornil¹  Jorge Heredia-moya²  Hernán Pessoa-mahana²  Boris Weiss-lópez¹ 

[1] ,Universidad de Chile Facultad de Ciencias Químicas y Farmacéuticas Departamento de Química Orgánica y FisicoquímicaSantiago,Chile

关键词: ¹H and 13C NMR;    HMBC;    CIGAR-HMBC;    IMPEACH-MBC;    5J C;    H;    acrylic acid ethyl esters;    chromone;   

DOI  :  10.1590/S0103-50532005000400028

来源: SciELO

【 摘 要 】

A systematic study about the long-range correlations observed in the HMBC spectra of a series of cis and trans 3-(4-oxo-4H-chromen-3-yl)-acrylic acid ethyl esters, and 5-hydroxy derivatives, was carried out. The results were compared with those observed in IMPEACH-MBC and CIGARHMBC spectra. An uncommon 5J C,H between the methyl protons and the Ca to the carbonyl group was observed in these systems as well as in ethyl chrotonate. The complete assignments of the ¹H and 13C NMR spectra are provided.

【 授权许可】

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