Dergiler / Turkish Journal of Chemistry / 2012 / Cilt: 36 - Sayı: 1

Four-component synthesis of 1,3,4-oxadiazole derivatives from N-isocyaniminotriphenylphosphorane, aromatic carboxylic acids, aromatic bis-aldehydes, and secondary amines

Four-component synthesis of 1,3,4-oxadiazole derivatives from N -isocyaniminotriphenylphosphorane, aromatic carboxylic acids, aromatic bis-aldehydes, and secondary amines

Sayfa
81–91
DOI
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Özet

The 1:1 iminium intermediate generated by the addition of a secondary amine to aromatic bis-aldehydes (isophthalaldehyde and terphthalaldehyde) is trapped by the N-isocyaniminotriphenylphosphorane in the presence of a aromatic carboxylic acid derivative, which leads to the formation of corresponding iminophosphorane intermediate. Then disubstituted 1,3,4-oxadiazole derivatives are formed via intramolecular aza-Wittig reaction of the iminophosphorane intermediates. The reactions were completed in neutral conditions at room temperature and the corresponding disubstituted 1,3,4-oxadiazole derivatives were produced in excellent yields.

Abstract

The 1:1 iminium intermediate generated by the addition of a secondary amine to aromatic bis-aldehydes (isophthalaldehyde and terphthalaldehyde) is trapped by the N-isocyaniminotriphenylphosphorane in the presence of a aromatic carboxylic acid derivative, which leads to the formation of corresponding iminophosphorane intermediate. Then disubstituted 1,3,4-oxadiazole derivatives are formed via intramolecular aza-Wittig reaction of the iminophosphorane intermediates. The reactions were completed in neutral conditions at room temperature and the corresponding disubstituted 1,3,4-oxadiazole derivatives were produced in excellent yields.

Anahtar kelimeler: N-isocyaniminotriphenylphosphorane, aromatic carboxylic acid, aromatic bis-aldehydes, 1, 3, 4-oxadiazole, aza-Wittig reaction, secondary amine